GEOLOGIC MAP OF THE
WILLIAMSBURG 7.5-MINUTE QUADRANGLE,
SIERRA COUNTY, NEW MEXICO
By
Andrew P. Jochems and Daniel J. Koning
December 2015
New Mexico Bureau of Geology and Mineral Resources
Open-file Digital Geologic Map OF-GM 250
Scale 1:24,000
This work was supported by the U.S. Geological Survey, National Cooperative Geologic
Mapping Program (STATEMAP) under USGS Cooperative Agreement 06HQPA0003
and the New Mexico Bureau of Geology and Mineral Resources.
New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of
Mining and Technology, 801 Leroy Place, Socorro, New Mexico, 87801-4796
The views and conclusions contained in this document are those of the author and
should not be interpreted as necessarily representing the official policies,
either expressed or implied, of the U.S. Government or the State of New Mexico.
1
CONTENTS
EXECUTIVE SUMMARY..............................................................................................................................................3
INTRODUCTION.............................................................................................................................................................4
GEOLOGIC SETTING....................................................................................................................................................5
STRATIGRAPHY..............................................................................................................................................................6
PRECAMBRIAN AND PALEOZOIC ROCKS...........................................................................................6
QUATERNARY-TERTIARY BASIN-FILL...................................................................................................8
Western piedmont of the Palomas Formation.....................................................................................8
Eastern piedmont of the Palomas Formation......................................................................................15
Axial-fluvial facies of the Palomas Formation....................................................................................16
Palomas Formation thickness and coarsening trends........................................................................18
QUATERNARY HISTORY (POST-PALOMAS FORMATION).............................................................18
STRUCTURAL GEOLOGY...........................................................................................................................................20
HYDROGEOLOGY.........................................................................................................................................................24
ACKNOWLEDGEMENTS............................................................................................................................................25
REFERENCES...................................................................................................................................................................26
Appendix A...........................................................................................................................................................................31
Appendix B...........................................................................................................................................................................46
Appendix C...........................................................................................................................................................................60
Appendix D..........................................................................................................................................................................132
2
EXECUTIVE SUMMARY
of well-sorted, quartzose sand with subordinate well
rounded gravel of diverse lithologies that interfinger
with both the western and eastern piedmont in a 3-5 km
belt centered on the modern Rio Grande. The lower 35
m of the axial deposits contain a horse tooth identified
by Gary Morgan (NM Museum of Natural History and
Science) as belonging to the species Neohipparion eurystyle,
which is restricted to 5.3-4.9 Ma strata.
The Williamsburg quadrangle is located in the eastern
part of the Palomas basin, an east-tilted half graben in the
southern Rio Grande rift, and includes all of the village of
Williamsburg and the western part of the city of Truth or
Consequences. The Palomas basin is bounded on the west
by the Sierra Cuchillo, Salado Mountains, and Animas
Hills. To the east, it is bordered by the Mud Springs
Mountains and Caballo Mountains. The oldest rocks are
Proterozoic plutonic rocks in the easternmost part of the
map area that include granite as well as lesser amounts of
amphibolite, gneiss, and schist. Cambrian to Ordovician
rocks unconformably overlie plutonic lithologies and
include a 200 m package of quartzose sandstone, dolomitic
limestone, and dolostone deposited in lower shoreface to
shallow marine shelf settings (Seager and Mack, 2003).
Proterozoic and Paleozoic rocks are down-dropped along
the Hot Springs fault and not exposed in the rest of the
quadrangle. Tertiary-Quaternary sediment dominates
the quadrangle, which overlies the deepest part of the
Palomas basin (Gilmer et al., 1986). Inferred Mioceneage basin fill is observed only in limited exposures
along the northern margin of the quadrangle. In the
deepest well on the quadrangle, the Barney Iorio Fee #1,
Miocene-age strata of the Rincon Valley Formation is
interpreted to extend from 175 m to the bottom of the
well (640 m). Relatively well-exposed Plio-Pleistocene
basin-fill of the Palomas Formation overlies the Rincon
Valley Formation. Younger deposits in the quadrangle
include a well-defined suite of six middle-late Pleistocene
Rio Grande terraces and Holocene valley-floor deposits
radiocarbon-dated at ~11 ka, ~2.5 ka, and 0.6-0.3 ka. The
Palomas Formation and latest Quaternary valley fills host
the most important aquifers in the study area.
The western piedmont facies of the Palomas Formation
can be subdivided into six conformable units. The lowest
(QTpwlt) includes 6-51 m of transitional pebbly channelfills and extra-channel deposits observed only in lithologic
well logs from the northern half of the quadrangle. Above
that lies the lower unit (QTpwl), consisting of ~20-80
m of coarse channel-fills. The middle unit (QTpwm)
is dominated by fine-grained strata (fine sand and silt),
whose uppermost part contains a fossil assemblage
interpreted at 3.0-2.6 Ma (Morgan and Lucas, 2012). This
middle unit is separated from an upper package by ≤35 m
of mud and sand containing 2.5-2.0 Ma vertebrate fossils
(QTpwt). The upper package is comprised of a lower unit
containing up to 45 m of ≥60% clayey-silty fine sand
and silt and ≤60% coarse channel-fills (QTpwu), and an
upper unit consisting of 2-45 m of amalgamated channelfill complexes (QTpwuc). The latter commonly features
1-2 m of pedogenic carbonate (stage III-IV morphology)
underlying the gently sloping aggradational surface of the
Palomas Formation, the ~0.8 Ma Cuchillo surface, which
extends throughout the western part of the quadrangle
(McCraw and Love, 2012).
Structures in the Williamsburg quadrangle are mostly
limited to the eastern half of the map area where the Hot
Springs and Caballo fault systems merge. These highangle, west-down normal fault zones separate the eastThe Palomas Formation was deposited by: (1) large tilted Caballo block from the Palomas basin to the west.
hanging wall distributary fan systems emanating from the The Hot Springs fault features Proterozoic and Paleozoic
eastern foothills of the Black Range (western piedmont rocks in its footwall but also deforms deposits of the
facies); (2) small footwall alluvial fans draining the upper Santa Fe Group and Palomas Formation. This
western escarpment of the Caballo Mountains (eastern implies Plio-Pleistocene vertical movement along the
piedmont facies); and (3) the ancestral Rio Grande. The fault, in agreement with earlier interpretations (Mason,
western piedmont is distinguished from footwall-derived 1976; Lozinsky, 1986).
eastern piedmont primarily by clast composition. Volcanic
lithologies dominate the western piedmont sediment The west-down Williamsburg fault likely represents a
whereas Paleozoic sedimentary clasts and granite northern extension of the Caballo fault system. It cuts
dominate eastern piedmont sediment. Furthermore, Holocene deposits south of Truth or Consequences
there is lesser cementation in the western piedmont (Foley et al., 1988) before bending abruptly to the
sediment (Mack et al., 2000) and a greater proportion of northwest. We interpret that this fault directly links
coarse-grained beds in the eastern piedmont sediment. with the Mud Springs fault at the mouth of Mud
Axial-fluvial facies of the ancestral Rio Grande consist Springs Canyon. Though the fault is buried at that
3
location, this interpretation is supported by stratigraphic
and age constraints: (1) correlation of lower western
piedmont deposits of the Palomas Formation exposed
in the footwall to buried hanging wall strata at 73-183
m depths in Truth or Consequences municipal wells
6, 7, and 8; and (2) paleontologic and radiometric data
indicating that exposed footwall strata are 5.3-4.8 Ma
and topographically lower, exposed hanging wall strata
are 3.0-2.6 Ma in age. Estimated post 4.5 Ma vertical
throw along the Mud Springs fault on the quadrangle is
190-200 m. Total throw along the Williamsburg segment
is unconstrained; Holocene fault ruptures have produced
scarps averaging 2.5-3 m in height perhaps as recently as
~2 ka (Foley et al., 1988).
INTRODUCTION
This report accompanies the Geologic Map of the
Williamsburg 7.5-Minute Quadrangle, Sierra County,
New Mexico (NMBGMR OF-GM 250). Its purpose is
to discuss the geologic setting and history of this area,
and to identify and explain significant stratigraphic and
structural relationships uncovered during the course of
mapping.
The Williamsburg quadrangle is located in the eastern
part of the Palomas basin and includes all of the village
of Williamsburg and the western part of the city of Truth
or Consequences (Fig. 1). The map area is bisected by
Interstate 25 (I-25) and the south-flowing Rio Grande.
The western part is dominated by a gently sloping surface
(the Cuchillo surface; see below) that is cut by numerous
arroyos and canyons. From north to south, these western
drainages include Mud Springs Canyon, Cañada Honda,
Palomas Creek, King Arroyo, and Kelly Canyon (Fig.
1). The eastern part of the map area consists of the Rio
Grande floodplain and, to the east, hilly terrain extending
eastward to the foot of the Caballo Mountains. The Rio
Grande floodplain is broad (3 km, 2 mi) in most of the
quadrangle, but narrows to 150-600 m (500-2000 ft) in
two places: 1) the northeast corner of the quadrangle,
and 2) near the middle of the quadrangle between the
opposing alluvial fans of Palomas Creek and Red Canyon,
the latter draining the Caballo Mountains. The highest
location in the quadrangle is 1473 m (~4830 ft) above
sea level (asl) along its northern border in sec. 4, T. 14 S.,
R. 5 W. The lowest point is 1279 m (~4195 ft) asl where
the Rio Grande exits the quadrangle. Exposures are
readily accessed by county roads extending up canyons
to the west of I-25, and numerous roadcuts expose strata
Figure 1. Relief map showing major physiographic features of the
Palomas basin and surrounding areas. The basin is bordered on the
east by the Caballo Mountains and on the west by the Animas-Salado
uplifts and Sierra Cuchillo (not shown). Williamsburg quadrangle is
outlined in red on relief map. Inset map shows location in Sierra
County, New Mexico; blue line is the Rio Grande. Abbreviations
for local communities: Cab = Caballo, Cuc = Cuchillo, LP = Las
Palomas, TorC = Truth or Consequences, W = Williamsburg.
along I-25 and NM-187. Access to exposures east of the
Rio Grande is via unimproved roads that connect with
Turtleback Avenue in Truth or Consequences.
The Williamsburg quadrangle (and most of the Palomas
basin) has an arid climate. The summer months (June
through August) experience average temperature
highs of 93-96° F and average lows of 63-67° F. In the
winter months (December through February), average
temperature highs are 55-63° F and average lows are 2731° F. Average yearly precipitation is 25.5 cm (10 in), of
which 8.4 cm (3.3 in) accumulates as snowfall. Over half
of the mean annual precipitation (13.7 cm) falls during
the North American monsoon in the months of July
4
through September. All climate data listed above are from GEOLOGIC SETTING
the Truth or Consequences station (ID# 299128) in the
The Williamsburg 7.5-minute quadrangle is located in the
NWS Cooperative network and averaged over the years
southern Rio Grande rift, a series of en echelon basins
of 1951-2012 (Western Regional Climate Center, 2015).
stretching from northern Colorado to northern Mexico
Early geologic mapping and reconnaissance work in the (Chapin and Cather, 1994). The quadrangle includes
Palomas basin was done by Gordon and Graton (1907), the eastern part of the Palomas basin, an east-tilted
Gordon (1910), and Harley (1934). Kelley and Silver half-graben filled with Miocene through Pleistocene
(1952) produced a benchmark geologic map and report of sediment (Figs. 1-2). The western border (i.e. hanging
the Caballo Mountains that included some of the adjacent wall) of the Palomas basin is defined by the Animas Hills
basin-fill and structures in the Williamsburg quadrangle. and Salado Mountains (Fig. 1), east-dipping fault-block
Seager and Mack (2003) summarized the geology of
the Caballo Mountains, with much discussion on the
Palomas Formation and paleogeographic interpretations
of the Palomas basin. Geologic maps were prepared at
1:24,000 scale for several of the surrounding quadrangles:
Apache Gap and Caballo (Seager and Mack, 2005),
Cuchillo (Maxwell and Oakman, 1990), Elephant Butte
(Lozinsky, 1986), and Palomas Gap (formerly Caballo
Peak; Mason, 1976). Foster (2009) mapped the northern
~1 km of the Williamsburg quadrangle at 1:12,000 as part
of a thesis on basin-fill stratigraphy surrounding the Mud
Springs Mountains north of Williamsburg. The Truth or
Consequences-Williamsburg area has also been the focus
of several studies on groundwater conditions and/or
geothermal resources including those of Murray (1959),
Cox and Reeder (1962), and more recently Person et al.
(2013).
Numerous studies by Greg Mack and Bill Seager (both of
New Mexico State University) and their colleagues shed
much light on the Palomas basin and its Plio-Pleistocene
basin-fill, the Palomas Formation. These studies range
from geochronologic (Seager et al., 1984; Mack et al., 1993;
Mack et al., 2009) and sedimentologic and stratigraphic
(e.g., Mack et al., 2002, 2008) to investigations of controls
on sedimentation (Mack and Seager, 1990; Mack et
al., 1994, 2006; Mack and Leeder, 1999) and soils and
paleoclimate (Mack and James, 1992; Mack et al., 1994,
2000). These works are cited frequently in the discussion
that follows.
Figure 2. Structure map of the Palomas basin with simplified geology
from New Mexico Bureau of Geology and Mineral Resources (2003).
Williamsburg quadrangle is outlined in red. Numbers correspond to
faults discussed in text: 1 = Mud Springs fault, 2 = Williamsburg
fault, 3 = Hot Springs fault, and 4 = Northern Caballo fault. Unit
designations are as follows: Qal = Quaternary alluvium, QTs =
Tertiary-Quaternary basin-fill, Tsf = Santa Fe Group (pre-dating
Palomas Formation), Tb = Pliocene basalt, Tvs = Eocene-Oligocene
volcanic and volcaniclastic, undivided, K = Cretaceous sedimentary,
undivided, Ki = Cretaceous intrusive, Kia = Cretaceous intrusive/
andesite, undivided, Pz = Paleozoic, undivided, and XY = Paleo- to
Mesoproterozoic, undivided. Abbreviations for local communities
(black dots) as in Figure 1.
This report includes a summary of the geologic setting
before describing mapped units and their depositional
settings by age, oldest to youngest. The structural geology
of the area is discussed, as are hydrogeologic implications
for mapped basin-fill. Clast counts, imbrication
measurements, radiocarbon data, and detailed unit
descriptions are provided as appendices.
5
uplifts composed primarily of Paleozoic sedimentary development.
and Eocene-Oligocene volcanic bedrock. For simplicity,
these ranges are referred to as the Animas-Salado uplifts
in this report.
STRATIGRAPHY
The eastern edge of the Palomas basin coincides with the
master fault system of the east-tilted Palomas half-graben.
This fault system includes the Caballo, Hot Springs,
Williamsburg, and Mud Springs faults (Fig. 2; Seager
and Mack, 2003). The footwall uplifts of this master
fault system, the Caballo and Mud Springs Mountains,
are east-dipping fault blocks cored by Paleozoic to
Mesoproterozoic plutonic rocks overlain by as much
as 1300 m of Paleozoic strata, mostly marine in origin
(Seager and Mack, 2003). Maximum displacement along
the Caballo fault is estimated at ~6.5 km based on gravity
data (Keller and Cordell, 1983; Gilmer et al., 1986) and
exposed thicknesses of Precambrian and Phanerozoic
packages in the Caballo Mountains (Seager and Mack,
2003). The Caballo fault system merges with the westdown Hot Springs fault near the eastern quadrangle
boundary, the latter continuing northward alongside the
northern Caballo Mountains (Fig. 2). The Mud Springs
fault wraps around the western foot of the Mud Springs
Mountain and continues as the Williamsburg fault toward
the eastern boundary of the quadrangle.
PRECAMBRIAN AND PALEOZOIC ROCKS
Precambrian rocks are exposed in the footwall of the
Hot Springs fault as well as along the Rio Grande in
the northeast corner of the quadrangle. These rocks
are primarily granite but include smaller bodies of
granitic gneiss, quartzofelspathic schist, metasiltstone,
and amphibolite. The latter occurs as pods ≤20 m
across that are either roof pendants or xenoliths in a
Plio-Pleistocene basin-fill of the Palomas Formation
dominates the Williamsburg quadrangle and is
differentiated on the basis of texture and clast lithology.
Coarse-grained gravels found east of the Rio Grande
were deposited in alluvial fans extending from the
western escarpment of the Caballo Mountains (Fig. 3).
Consistent with their source area, clasts in these gravels
are dominated by limestone, dolostone, and granite.
The piedmont deposits in the western two-thirds of
the quadrangle contain gravels composed of felsic- to
intermediate-dominated volcanic rocks. These beds dip
toward the east and are capped in many places by a gently
inclined (≤1.5°) plain known as the Cuchillo surface. This
surface is constructional in the Williamsburg quadrangle
and dates to ~0.8 Ma (Lozinsky, 1986; Lozinsky and
Hawley, 1986b; Mack et al., 1993; McCraw and Love,
2012). Intertonguing with both the western and eastern
piedmont deposits are axial facies of the ancestral Rio
Grande, exposed in a 3-5 km wide belt centered on
the modern day river (Fig. 3). The Rio Grande and its
tributaries began incising into the Palomas Formation
~0.8 Ma, alternating with periods of backfilling that
resulted in a series of inset terrace deposits distinguished
by landscape position, texture, clast lithologies, and soil
Figure 3. Distribution of Palomas Formation facies in the
Williamsburg quadrangle and surrounding areas. Axial-fluvial facies
are exposed in a ~3-5 km belt centered on the modern Rio Grande
valley. Facies distributions off quadrangle modified from Foster
(2009) and Mack et al. (2012) to the north, and Seager and Mack
(2005) to the south. Abbreviations for local communities (black dots)
as in Figure 1.
6
larger granitic pluton; the protolith for these rocks was
likely basalt (Bauer and Lozinsky, 1986). Granitic rocks
(=g) exposed in the quadrangle are dominantly pink
and hypidiomorphic granular with large phenocrysts
of microcline, plagioclase, biotite, and quartz (Fig. 4).
The granitic rocks were initially thought to belong to
the Caballo granite exposed in the southern half of the
Caballo Mountains (Condie and Budding, 1979; Bauer
and Lozinsky, 1986). However, Seager and Mack (2003)
suggested that this granite may have formed from its own
pluton because it lacks pegmatites that are observed in
the Caballo granite. Field relationships near Longbottom
Canyon south of the quadrangle imply that the northern
pluton is somewhat younger than adjacent basement
rocks. The latter include granodiorite dated at 1.47 ±
0.21 Ga and gneiss dated at 1.67 ± 0.16 Ga using U-Pb
isotopes from zircon (Amato and Becker, 2012). The
Caballo granite found in the southern part of the range
has been dated at 1.3-1.45 Ga using Rb-Sr and U-Pb
isotopes (Muehlberger et al., 1966; Amato and Becker,
2012).
prominent dark band visible above pinkish-red granite in
the lower slopes of the Caballo Mountains.
The Bliss Formation is gradational with cherty limestone
of the overlying El Paso Formation. The lower ~50 m of
the El Paso Formation is the Sierrite Limestone (Oeps),
consisting of sparsely fossiliferous packstone with vertical
burrows in-filled by dolomite. This unit is overlain by
65 m of limestone (cherty wackestone to grainstone)
comprising the Bat Cave Member (Oepb), which features
common stromatolites forming thin algal mats or domal
structures up to 30 cm in diameter (Fig. 5). The El Paso
Formation was deposited below wave base on a shallowmarine shelf and represents up to five transgressiveregressive cycles (Seager and Mack, 2003; Mack, 2004).
Figure 5. Algal mats in Bat Cave Member of the El Paso Formation.
Located east of Rio Grande in footwall of Hot Springs fault. Pen is
15 cm long.
The middle to upper Ordovician Montoya Formation
disconformably overlies the El Paso Formation. It is
divided into the Aleman Member (Oma) and a basal unit
informally designated the Lower Member (Oml). The
Lower Member consists of poorly-sorted quartz arenite
underlying cherty dolostone. These beds correspond to
the Cable Canyon Sandstone and Upham Dolomite,
respectively, of Kelley and Silver (1952), and were not
mapped separately on this quadrangle due to their low
composite thickness (only 37 m). The Cable Canyon
Sandstone has been interpreted as representing openmarine sand bars formed by the reworking of sand dunes
during a transgressive event (Bruno and Chafetz, 1988;
Pope, 2004). Dolostone of the Upham Member was
probably deposited on an open-marine carbonate ramp
(Pope, 2004).
Figure 4. Gneissic granite with well defined foliation. Located east
of Rio Grande in footwall of Hot Springs fault. Hammer is 28 cm
long.
Lower to middle Paleozoic rocks in the quadrangle were
deposited on a stable, epicratonal shelf with low rates of
sedimentation and subsidence. This shelf was subjected
to periodic inundation by shallow, tropical seas (Seager
and Mack, 2003). The oldest Paleozoic strata exposed
throughout southern New Mexico and west Texas is
the Cambro-Ordovician Bliss Formation (_Ob). This
unit consists of dark brown to black, cross-stratified,
quartzose sandstone containing peloidal glauconite,
and is the basal unit of an early eastward to northward
transgression (Mack, 2004). The Bliss Formation forms a The overlying Aleman Member of the Montoya Formation
7
consists of cherty dolostone with subordinate amounts of
limestone and jasperoid. Although sparsely fossiliferous in
the Williamsburg quadrangle, the articulate brachiopods
Rafinesquina and Zygospira were recovered from this
member in the Palomas Gap quadrangle to the east
(Mason, 1976). Pope (2004) suggests a shallow, openmarine origin for these strata.
Palomas Formation in the Williamsburg quadrangle are
found at NW¼ NW¼ sec. 30 and NE¼ SW¼ sec. 33, T.
14 S., R. 4 W (Lozinsky and Hawley, 1986a).
The Palomas Formation exhibits a variety of lithofacies,
from gravel-dominated channel-fills to clays, silts,
and fine sands representing extra-channel or eolian
deposition. In the Williamsburg quadrangle, the Palomas
is subdivided into three primary lithofacies: (1) westernderived piedmont deposited as distributary fan complexes
in the hanging wall of the Palomas basin (QTpw units),
(2) eastern-derived sand and gravel deposited on much
smaller fans emanating from the western escarpment of
the Caballo Mountains (QTpe units), and (3) axial-fluvial
sandy channel fills and fine floodplain deposits of the
ancestral Rio Grande (QTpa units). The distribution of
these facies in the Williamsburg quadrangle is shown in
Fig. 3. Although broad textural distinctions may apply to
each facies, the units are more easily differentiated using
lithologic composition of clasts, reflecting the source
area of a particular facies. QTpw units are composed of
volcanic sand and gravel originating in the Black Range
and Animas-Salado uplifts, QTpe sand and gravel are
dominated by carbonate and plutonic rocks derived
from the western Caballo Mountains, and QTpa channel
fills feature exotic clasts such as quartzite. This report
describes each facies in the order listed above. Detailed
unit descriptions are given in Appendix A, and clastcount and paleocurrent data are given in Appendices B
and C, respectively.
QUATERNARY-TERTIARY BASIN-FILL
Basins throughout the Rio Grande rift are characterized by
thick accumulations of clastic sediment (with subordinate
interbedded volcanic deposits) collectively known as the
Santa Fe Group (Kelley, 1977; Hawley, 1978; Gile et al.,
1981; Chapin and Cather, 1994; Connell, 2008). This
sediment was deposited during Rio Grande rift extension.
Specific age ranges for basin-fill packages depend on
location but generally include the late Oligocene through
early Pleistocene. Late Oligocene to middle Miocene
basin-fill is not exposed in the Williamsburg quadrangle
nor penetrated by the 2100 ft-deep Barney Iorio Fee #1
well. Reddish, fine-grained beds of sandstone, pebbly
sandstone, and clay (Tsupw, Tsubf) exposed along the
northern quadrangle boundary are likely correlative to
the upper Miocene Rincon Valley Formation of Seager
et al. (1971). These beds are located in the footwall of the
Mud Springs-Williamsburg fault and are not observed
elsewhere in the quadrangle. Relatively fine-grained
strata containing pink to red, sticky clays are correlated
to the Rincon Valley Formation in the Barney Iorio Fee
Western piedmont of the Palomas Formation
#1 well, where they extend from 578 ft to the bottom of
The transitional base of the lower western piedmont
the well (2100 ft).
facies of the Palomas Formation (QTpwlt) consists of
The basin-fill stratigraphy of the Williamsburg interbedded pebbly channel-fills and extra-channel
quadrangle is dominated by Plio-Pleistocene sediment deposits dominated by clayey-silty fine-grained sand
of the Palomas Formation, the uppermost unit of the (Fig. 6). This unit has a texture intermediate between
Santa Fe Group in the Palomas Basin (Lozinsky and the overlying and underlying units (QTpwl above, Tsubf
Hawley, 1986a, b). The term “Palomas” was first applied and Tsupw below). The apparent lack of aphanitic basalt
to outcrops of upper Santa Fe Group basin fill by clasts suggests that the unit pre-dates the 4.8-4.3 Ma
Gordon and Graton (1907), Gordon (1910), and Harley basalt flows found in the western Palomas basin (Seager
(1934). Lozinsky and Hawley (1986a) formally defined et al., 1984; Jochems et al., 2014; Jochems, 2015; Koning
the Palomas Formation. Detailed descriptions of the et al., 2015). It is relatively thin in outcrop (<10 m
unit are presented in Lozinsky and Hawley (1986a, b) thick) and subsumed into the base of the lower western
and Lozinsky (1986). Fossil data (summarized by Morgan piedmont unit (QTpwl) along the northern quadrangle
and Lucas, 2012), basalt radiometric dates (Bachman and boundary. Interpretation of well data suggests that the
Mehnert, 1978; Seager et al., 1984; Jochems, 2015), and unit thickens southward from a minimum of ~30 m in
magnetostratigraphic data (Repenning and May, 1986; Truth or Consequences city wells to as much as 51 m
Mack et al., 1993; Leeder et al., 1996; Mack et al., 1998; in the Barney Iorio Fee #1 well south of Palomas Creek
Seager and Mack, 2003) indicate an age range of ~5.0- (Tables 1 and 2).
0.8 Ma for the Palomas Formation. Type sections of the
8
Figure 6. Stratigraphic fence diagram composed from interpretations of lithologic logs for Truth or Consequences city wells 6, 7, and 8. See
geologic map for well locations.
Table 1. Location and subsurface stratigraphic data for select wells of the Truth or Consequences city well field.
Well ID
UTM Ea
UTM Na
Location
(TownshipRange-Sect)b
Well head
elev. (ft)
Total
Depth
(ft)
Stratum
Depth from
cuttings (ft)
Well No. 6
286318
3666768
6.3242-14S-4W
4241
520
Q(f )ayr
0-20
4221
Qayr/Qtr
20-90
4151
QTpwm
90-150
4091
Well No. 7
Well No. 8
286807
286003
3666755
3666770
6.423-14S-4W
6.32-14S-4W
4238
4239
610
620
Depth,
geophys.
logs (ft)
Elevation of
base (ft)
QTpwm-QTpa 150-180
margin
4061
QTpwm
180-220
4021
QTpwl
220-520
Qayr/Qtr
0-80
0-74
4164
QTpwm
80-260
74-250
3988
QTpwl
250-400
250-395
3843
QTpa
400-470
395-466
3772
QTpwl
470-520
466-506
3718
QTpwlt
520 to >610
506 to >610
<3628
Q(f )ayr
0-62
0-56
4183
QTpwm
62-225
56-246
3993
QTpwl
225-510
246-496
3743
QTpwlt
510 to >620
496 to >620
<3623
UTM Zone 13S, NAD83.
a
Well locations on subdivision of township and range sections. For example, a location of 1.1234-1S-1W indicates the SE quarter (4) of the SW quarter (3)
of the NE quarter (2) of the NW quarter (1) of section 1, Township 1 South, Range 1 West.
b
9
Table 2. Location and subsurface stratigraphic data for wells used in Cross-section A-A’.
Well ID
UTM Ea
UTM Na
Location
(TownshipRange-Sect)b
Well head
elev. (ft)
Total
Depth
(ft)
Stratum
Depth from
cuttings (ft)
Elevation of
base (ft)
Groundwater
depth (ft)
Barney Iorio
Fee #1
284759
3660416
25.41-14S-05W
4303
2100
Qayr
0-17
4286
90, 140, 193,
372, 543,
632, 1160,
1170/1200
QTpwm
17-70
4233
QTpa
70-193
4110
QTpwm
193-272
4031
QTpa
272-285
4018
QTpwm
285-407
3896
QTpwl
407-463
3840
QTpwlt
463-578
3725
Tsu
578 to
>2100
<2203
Qayr
0-41
4242
QTpwm
41-70
4213
QTpa
70 to >149
<4134
HS-00146
285052
3660102
25.441-14S-05W
4283
149
70
HS-00316
285153
3660003
25.44-14S-05W
4275
100
Qayr
70(?)
4205(?)
62
HS-00773
285456
3659896
30.333-14S-04W
4262
92
Qayr
0-59
4203
37
QTpwm
59 to >92
<4170
Qayr
0-32
4225
QTpwm
32-100
4157
QTpa
100-155
4102
QTpwm
155-225
4032
QTpa
225-246
4011
QTpwm
246 to >320
<3937
Qayr
0-42
4213
QTpwm
42-44
4211
QTpa
44 to
<4200
4209
HS-00033
HS-00663
285556
285656
3659995
3659896
30.33-14S-04W
30.334-14S-04W
4257
4255
320
55
HS-00648b
285671
3659732
31.112-14S-04W
4260
51
QTpwm
0 to >51
HS-00737
285848
3659682
31.121-14S-04W
4258
165
Qayr
0-18
QTpa
18 to >165
Qayr
0-16
4236
QTpa
16 to >92
<4160
HS-00729
286048
3659682
31.122-14S-04W
4252
92
NA
30
20
70
36
UTM Zone 13S, NAD83.
a
Well locations on subdivision of township and range sections. For example, a location of 1.1234-1S-1W indicates the SE quarter (4) of the SW quarter (3) of the
NE quarter (2) of the NW quarter (1) of section 1, Township 1 South, Range 1 West.
b
c
UTM location moved slightly from what was stated in well log to account for unreasonable position relative to topography
10
The contact between QTpwlt and the overlying lower
western piedmont (QTpwl) is sharp to gradational over
4-10 stratigraphic meters. QTpwl is only exposed on the
footwall of the Mud Springs-Williamsburg fault, where
it consists of stacked, pebbly to cobbly channel-fills (Fig.
7). In the subsurface on the hanging wall of this fault,
these channel fills are interbedded with subordinate,
light brown extra-channel deposits composed of clay, silt,
and very fine- to medium-grained sand. Volcanic clasts
are dominated by rhyolite with subordinate tuffs and
intermediate volcanic varieties. A small amount (≤5%)
of granite and Paleozoic clasts found in the northern part
of the quadrangle suggests mixing of distally derived
volcanic sediment with sediment sourced from local
bedrock exposed on the western flanks of the east-dipping
Mud Springs Mountains. There, QTpwl is correlative
with the “sedimentary, granitic, and metamorphic-clast
conglomerate facies assemblage” of Foster (2009) and
Mack et al. (2012). The presence of trace to 1% vesicular
basalt indicates that the unit post-dates the 4.8-4.3 Ma
basalt flows found in the western Palomas basin (Seager
et al., 1984; Jochems et al., 2014; Jochems, 2015; Koning et
al., 2015a). The lower western piedmont is 76-78 m thick
in Truth or Consequences city wells 7 and 8 (including an
intervening tongue of Rio Grande axial sediment in city
well #8; Table 1, Fig. 6), and thins southward to 17 m in
the Barney Iorio Fee #1 well (Table 2).
Beds of fine-grained sand and silt with subordinate (520%) tongues of pebbly sand and sandy pebble gravel
comprise the middle western piedmont facies (QTpwm).
Its base is not exposed on the quadrangle. This unit is
generally light colored (7.5YR 7/3; 6/ 3-4; 5-7.5YR 6-7/2),
and beds are often internally massive (Fig. 8). These beds
may contain sparse (3%) pebbles and up to 10% “floating”
medium to very coarse sand grains that are interpreted
as hyperconcentrated flows (Seager and Mack, 2003).
Prominent carbonate ledges may be observed in the
upper 10-20 m of the unit. Occasionally, coarse channelfills within this unit are sufficiently extensive to map
separately (QTpwmc), particularly in the southern part of
the quadrangle. Among many fossils collected by previous
workers from QTpwm are Paramylodon, a small ground
sloth, and the horse Nannippus (Tedford, 1981; Morgan
and Lucas, 2012). The co-occurrence of these species
suggests a late Blancan (~3.0-2.6 Ma) North American
Land Mammal age for the upper part of this unit (Fig. 9;
Morgan, 2008; Morgan and Lucas, 2012). Buried soils with
stage II-III carbonate morphology (nodules, tubules) are
common in muddy intervals of QTpwm (Fig. 10). These
Figure 7. Contact between axial-fluvial (QTpa) and lower western
piedmont facies (QTpwl) of the Palomas Formation just north of
Williamsburg quadrangle in downtown Truth or Consequences (sec.
33, T. 13 S., R. 4 W., Cuchillo 7.5’ quadrangle). Contact is locally
scoured up to 3 m. QTpwl consists of reddish, stacked channel-fills
and subordinate pebbly sand. Gravelly QTpa deposit represents first
incursion of ancestral Rio Grande into Palomas basin ~5 Ma.
horizonated paleosols typically feature two or more Bt,
Bk, and/or K horizons that formed due to vadose zone
pedogenesis (Mack et al., 2000). QTpwm interfingers
with axial-fluvial facies in wells along Palomas Creek and
Truth or Consequences city well #8, where individual
tongues are generally 9-37 m thick (Fig. 8; Tables 1 and
2). The middle western piedmont is approximately 4060 m thick in Truth or Consequences city wells. In the
southern quadrangle, exposed thicknesses coupled with
subsurface interpretations of the Barney Iorio Fee #1
11
Figure 8. West Williamsburg stratigraphic section. See Appendix A for detailed unit descriptions. Paleocurrent
measurements from clast imbrication. SW¼ SW¼ sec. 1 and NE¼ NE¼ sec. 12, T. 14 S., R. 5 W.
well indicate a total thickness of 120-150 m (including
tongues of Rio Grande axial fluvial facies).
The middle western piedmont underlies a transitional
zone (QTpwt) across the quadrangle. This unit has a
12
Equus sp., and a tooth of the extinct rabbit Sylvilagus hibbardi
that indicates a late Blancan (2.5-2.0 Ma) age for the
unit (G. Morgan, personal communication, 2014). This
age constraint is corroborated by magnetostratigraphic
data, which implies that QTpwt lies below the Olduvai
subchron (1.95-1.77 Ma) in the Las Palomas Area (Fig.
12; Mack et al., 1993, 1998; Leeder et al., 1996; Seager and
Mack, 2003). Transitional beds lie gradationally between
QTpwm and the upper western piedmont (QTpwu),
both in a vertical and lateral sense, with gradational
relationships particularly apparent west of I-25 and south
of Palomas Creek.
Figure 9. Contact between transitional (QTpwt) and middle
(QTpwm) western piedmont facies of the Palomas Formation along
I-25 roadcut just south of Mud Springs Canyon. Pebble-cobble gravel
just above contact is rare (<10%) in QTpwt deposit that otherwise
consists of silt-clay, very fine- to fine-grained sand, and slightly siltyclayey sand. QTpwm consists of pinkish silty sand with rare, thin
gravel stringers. Vertebrate fossils recovered from the top part of
QTpwm and described in Morgan and Lucas (2012) suggest a late
Blancan age of 2.7-2.5 Ma. Pack is ~0.6 m tall.
Figure 11. Carbonate ledge interbedded in transitional western
piedmont facies (QTpwt). Prominent ledges form marker beds that
are 0.5-1 m thick and are commonly massive and vuggy. Alternatively,
beds may be wavy and nonparallel due to lithification of root mats.
This bed appears to have collapsed into a small sinkhole. Pack is 0.6
m tall.
Figure 10. Stage II carbonate morphology in middle western
piedmont (QTpwm) exposed near the mouth of Kelly Canyon.
Vertically elongate carbonate tubules could have formed around
roots and/or burrows (Mozley, personal communication, 2015).
Forms Btk horizon in paleosols that also features slickensides and
wedge-shaped peds. Hammer is 28 cm long.
maximum thickness of 35 m and thins to the south where
it becomes too thin to differentiate. The transitional
facies are mostly fine-grained (silt and fine sand with
subordinate clay), and contain prominent marker beds of
pale yellowish pink (7.5YR 9.5/2) to pinkish white (5YR
8/2), massive carbonate (Figs. 8, 11) that envelops pebbles
and small cobbles in places. Root mats and laminations
are common in these beds, and have been interpreted
as spring (cienega) deposits formed at the medial-distal
alluvial fan interface (Mack et al., 2000). These intervals
are common south of King Arroyo. Fossils recovered
from QTpwt include gomphothere teeth, limb bones of
Figure 12. Comparison between paleomagnetostratigraphic section
from Las Palomas Creek (Mack et al., 1993) and Palomas Formation
unit interpretations from this study. Letters on left correspond to
chrons and subchrons: G = Gauss, M = Matuyama (chrons), and R =
Reunion, O = Olduvai (subchrons). Modified from figure 9 of Mack
et al. (1993) and figure 76 of Seager and Mack (2003).
The upper western piedmont (QTpwu) consists of clay, silt,
fine sand, and ≤60% pebbly to cobbly coarse channel-fills
(Fig. 13). This unit forms prominent, cliffy exposures on
13
Figure 13. Contact between upper (QTpwu) and upper coarse (QTpwuc) western piedmont facies of the Palomas Formation in Kelly
Canyon west of I-25. QTpwu consists of ~65% pinkish to reddish brown mudstone, silt, and silty sand and ~35% pebbly to cobbly channelfills. Total relief of exposure is ~20 m.
the south side of Palomas Creek. Clay-rich intervals impart
a distinctive reddish color (e.g. 5YR 4/4-6; Fig. 8) and
likely represent extra-channel (floodplain) depositional
settings. Internally massive, clayey to silty sand beds
locally contain scattered coarse sand and volcanic pebbles
and are interpreted as hyperconcentrated flow deposits
(Seager and Mack, 2003). Like QTpwm, fine-grained
intervals of QTpwu commonly feature paleosols with
Bt and Bk horizons. However, select beds with elongate
carbonate nodules parallel to bedding may have formed
due to a vertically shifting water table rather than vadose
zone pedogenesis (Mack et al., 2000). Gravelly channelfills in QTpwu contain up to 7% clasts of vesicular basalt;
this proportion decreases to the north. The lower contact
of QTpwu lies immediately above the Kelly Canyon
Local Fauna site, which features axial-fluvial strata ~2.62.0 Ma in age (Morgan et al., 2011; Morgan and Lucas,
2012). Given a similar late Blancan age for the underlying
transitional unit as well as magneostratigrapic data from
the Las Palomas area (Fig. 12; Mack et al., 1993, 1998;
Leeder et al., 1996; Seager and Mack, 2003), the age of
the upper western piedmont is tentatively estimated at
~2.5-1.8 Ma. This unit is 2-45 m thick.
horizon that is 1-2 m thick where not significantly
eroded. This surface soil generally exhibits stage III to IV
carbonate morphology (Seager and Mack, 2003; McCraw
and Love, 2012), and is correlative to the Jornada I and La
Mesa surfaces of the Camp Rice Formation in the Rincon
and Mesilla basins to the south (Gile et al., 1981). The
age of the youngest coarse upper western piedmont is
constrained by magnetostratigraphy at ~0.8 Ma (Mack et
al., 1993, 1998, 2006; Mack and Leeder, 1999). The upper
coarse western piedmont has a maximum thickness of
45 m.
Lying above QTpwu are coarse, amalgamated, laterally
continuous channel-fill complexes (QTpwuc) with 1-15%
clasts of vesicular basalt (Fig. 8). The coarse channel-fills
commonly feature basal scour surfaces with up to 1 m of
relief (Fig. 14). Low-angle and trough cross-stratification,
lateral accretion cross-stratification, and clast imbrication
are common. Paleoflow indicated by clast imbrication is
typically east-southeast (Appendix C). QTpwuc underlies
the Cuchillo surface, which is marked by a petrocalcic
Figure 14. Scoured contact between upper coarse (QTpwuc) and
upper (QTpwu) western piedmont facies of the Palomas Formation.
Here, local relief of scour is less than ~0.5 m. QTpwuc consists of
vague, tabular to lenticular beds of clast-supported sandy gravel with
minor cross-stratification up to ~0.5 m thick. Upper QTpwu features
weakly developed argillic horizon of a paleosol. Largest clasts are
20-30 cm across.
14
Figure 15. Proximal alluvial fan facies of the eastern piedmont of the Palomas Formation (QTpe). Strongly (sparry) carbonate cemented
pebble gravel forms well defined erosional surface that may be planar (A) to scoured (B) on more weakly consolidated pebble gravel and silt.
Progradational relationships are commonly observed in QTpe exposures. Tape is 2 m tall.
Eastern piedmont of the Palomas Formation
The eastern piedmont facies (QTpe) is differentiated
from western-derived piedmont by three criteria: (1)
a predominance of coarse-grained beds; (2) common
sparry calcite cement; and (3) the presence of Paleozoic
carbonate and Proterozoic plutonic clasts. Cementation
and sedimentary structures vary according to relative
fan position (proximal, medial, and distal) in the eastern
piedmont. Proximal deposits consist of poorly sorted,
sandy pebble-cobble gravel in tabular beds (Fig. 15).
These intervals rarely feature cross-stratification and
are cemented by authigenic carbonate precipitated from
shallow groundwater or gully-bottom cementation. Both
cementation types are non-pedogenic, and the latter
forms when bicarbonate-rich runoff evaporates from
gravelly stream beds (Mack et al., 2000; Mack and Seager,
2003). Medial deposits consist of massive or imbricated
to planar cross-stratified sand and gravel. Occasional
paleosols in finer-grained medial facies may feature
illuviated clay (Bt) horizons above clay and carbonaterich horizons (Btk). Distal deposits consist of moderately
sorted coarse channel fills (with pebbles or pebblecobbles) interbedded with matrix-supported silt or sand
beds. Paleosols with Btk to K horizons are common in
distal silt beds. In the northern part of the quadrangle,
the eastern piedmont commonly interfingers with axialfluvial facies. Just south of the quadrangle, the base of
the eastern piedmont deposits is interbedded with a
basalt dated at 3.1 ± 0.1 Ma (K/Ar; Seager et al., 1984),
implying a temporal correlation with western piedmont
units QTpwm, QTpwt, QTpwu, and QTpwuc. This unit
has a maximum exposed thickness of 110 m.
(QTpef). Buried soils are common in this unit and include
stage I to II+ carbonate morphology with Btk, Bk, and
K horizons up to ~1 m thick (Fig. 16). In addition to its
obvious textural distinction from the undivided eastern
piedmont, QTpef contains no clasts of red Abo Formation
siltstone and fine-grained sandstone, distinguishing it
from the Red Canyon paleo-fan facies (described below).
The unit underlies and likely locally interfingers with
QTpe. It may also interfinger with axial-fluvial facies at
depth. Its maximum thickness is estimated at 140 m from
cross-section relations in the Red Canyon area, though it
thins northward to ~30 m.
Figure 16. Stage II carbonate morphology observed in fine-grained
facies of the eastern piedmont of the Palomas Formation (QTpef).
Well-developed carbonate tubules indicate long-lasting stability
before the deposit was eroded by younger alluvial fan gravel (upper
part of photo). Pack is 0.6 m tall.
Prominent topographic benches flanking Red Canyon are
South of Red Canyon, fine-grained exposures of mostly underlain by strata of the Red Canyon paleo-alluvial fan
massive clay and silty sand with <40% gravel can be (QTper). This unit rises above adjoining ridges underlain
mapped as a fine-grained subunit of the eastern piedmont by QTpe and is clearly delineated in the field and aerial
imagery by its reddish hues. Red Canyon paleo-fan facies
15
Figure 17. Typical exposure of paleo-Red Canyon alluvial fan (QTper) facies. Unit includes thick (up to 30 m) sequences of channel-fills
and/or fanglomerate with abundant clasts of Permian Abo Formation. Subordinate to these facies are tabular silt and sand beds with floating
pebbles, representing deposition on floodplains or by hyperconcentrated flows. NW¼ sec. 4, T. 15 S., R. 4 W.
are characterized by siltstone, sandstone, and sandy
pebble-cobble-boulder conglomerate in multi-story beds
(Fig. 17). Their red color (5YR 4-5/6 to 5-7/4) is derived
from abundant (up to 30%) clasts sourced from the
Permian Abo Formation, exposed in the headwaters of
Red Canyon. Scoured contacts on underlying sandstone
and siltstone beds are common. A stratigraphic section
measured by Lozinsky and Hawley (1986a) includes
an ash 17 m below the top of Red Canyon piedmont
(QTper) correlated with 1.2-1.45 Ma Cerro Toledo tephra
units originating from the Jemez volcanic field (Izett
et al., 1981; Spell et al., 1996). The top of Red Canyon
piedmont features stage III-IV carbonate morphology
and correlates to the Cuchillo surface (Lozinsky and
Hawley, 1986a; Mack et al., 1993). QTper interfingers
with at least two tongues of axial-fluvial strata along the
lower 1.7 km of modern Red Canyon (Fig. 18). The Red
Canyon paleo-fan facies is 60-140 m thick.
Axial-fluvial facies of the Palomas Formation
Nearly every Palomas Formation piedmont unit
interfingers with axial-fluvial facies of the ancestral Rio
Grande (QTpa). This lithofacies is characterized by crossstratified, well sorted, well rounded, quartzose sand
Figure 18. Interfingering between axial-fluvial facies (QTpa) and alluvial fan facies of Red Canyon (QTper), both of the Palomas Formation.
Slip along the Caballo fault ~3 km to the west of this exposure (towards the left in photo) likely accounts for onlapping relationships between
the two units (e.g., Mack and Leeder, 2009). Total relief of exposure is ~20 m. NE¼, NW¼, sec. 32, T. 14 S., R. 4 W.
16
Pebbly to silty sand with subordinate mudstone floodplain
deposits (QTpaf) are the most common axial facies. The
presence of reddish to olive, massive mudstones in this
unit indicate low-energy floodplain environments (Fig.
19). Scattered concretions of manganese-rich material
may be observed in these facies. Fine-grained axial
deposits near the mouth of Kelly Canyon have yielded
many fossils, including salamanders (Amystoma sp.), frogs
(Rana sp.), and other freshwater vertebrates that could
have inhabited slack-water environments (G. Morgan,
Figure 19. Floodplain axial-fluvial facies (QTpaf) overlain by a personal communication, 2015). A fossil of the extinct
channel-fill of the middle western piedmont facies (QTpwmc). muskrat Ondatra idahoensis was also recovered from these
Frequent channel avulsions of the ancestral Rio Grande resulted in beds, indicating a late Blancan (~2.6-2.0 Ma) age for axial
overall poor preservation of axial floodplain facies (Seager and Mack, facies at that location (Morgan and Lucas, 2012).
2003). SW¼ NW¼ sec. 12, T. 15 S., R 5 W.
Coarse-grained axial facies (QTpac) consist of sandy
pebble-cobble and pebble-cobble-boulder gravel/
conglomerate deposited in laterally extensive channelfill complexes. Lateral accretion sets are occasionally
observed, and strongly indurated exposures sometimes
preserve flute casts. Planar to trough cross-stratified
sandy beds are interpreted as channel sandbars (Fig.
20). Ellipsoidal concretions are observed where beds
are cemented east of the Rio Grande (Fig. 21), and may
have formed in the direction of groundwater flow downgradient of decaying organic matter (Mozley and Davis,
2005). Paleocurrent directions in imbricated gravel beds
containing a heterolithic gravel assemblage of Tertiary
volcanics, Cretaceous sandstone, Paleozoic carbonates,
and quartzite. Limestone, sandstone, and siltstone
constitute a greater proportion (up to 80% total) of clasts
in basal beds; volcanics and quartzite increase up-section.
This unit was deposited by the ancestral Rio Grande in
a 3-5 km belt centered on the modern Rio Grande valley
throughout the Palomas basin, and commonly exhibits
field relationships suggesting toe-cutting of footwallderived alluvial fans (Seager et al., 1982; Lozinsky and
Hawley, 1986a; Seager and Mack, 2003; this study). Two
subunits have been differentiated: QTpaf and QTpac.
Figure 20. Trough cross-stratification in axial-fluvial facies (QTpa) of the Palomas Formation. White lines show apparent (outcrop) direction
of individual foresets. Compass for scale (black circle) is 10 cm in diameter. NW¼ SW¼ sec. 16, T. 15 S., R. 4 W.
17
Figure 21. Concretions in axial-fluvial facies (QTpa) of the Palomas Formation. (A) QTpa channel gravel scouring fine- to medium-grained
axial sand with concretions (white box). (B) Close-up profile view of concretions. Concretions are commonly ellipsoidal and up to 30 cm
across. They typically follow paleocurrent directions and likely form from plumes of groundwater in well sorted, permeable sand (Mozley
and Davis, 2005). Hammer is 28 cm long.
average south-southeast, though imbricated clasts give
south-southwest paleoflow directions in the lower 30
m of the unit along the northern quadrangle boundary.
Manganese coats on clasts are common. Coarse axial
deposits typically exhibit basal scour contacts on finergrained sediment with up to 3 m of relief. A tooth of
the late Hemphillian horse Neohipparion eurystyle, collected
from spoil piles just north of the quadrangle, suggests
an age of 5.3-4.9 Ma for the lower 35 m of ancestral Rio
Grande gravels (G. Morgan, personal communication,
2015). Thus, the ancestral Rio Grande appears to have
entered the Palomas basin at approximately 5 Ma.
Inspection of cross-section A-A’ indicates a maximum
preserved thickness of 250 m for the axial facies on the
Williamsburg quadrangle.
In addition to a pattern of eastward thickening, the
Palomas Formation also exhibits an upward-coarsening
trend from the QTpwl-QTpwm contact; this trend is
observed throughout the Palomas basin (Grundwald,
1990; Jochems, 2015; Koning et al., 2015). Though
perhaps related in part to tectonic tilting and the large size
of hanging wall catchments, this pattern may be primarily
attributed to paleoclimatic drivers in the surrounding
mountain ranges that promoted high effective discharge
and low sediment/water ratios, conditions favorable
for high erosion rates in headwater areas (Mack et al.,
2012). Changes in such conditions with climate shifts,
such as glacial-interglacial transitions, have been welldocumented (Bull, 1991), and have been invoked for
similar coarsening trends observed in rift-fill packages
elsewhere in New Mexico (Koning et al., 2002).
Palomas Formation thickness and coarsening trends
Initially thought to be 100-131 m thick (Lozinsky and
Hawley, 1986a), our work suggests a total thickness
of 150-350 m for the Palomas Formation in the
Williamsburg quadrangle. This range is based on the
measured thicknesses of QTpw units in the Truth
or Consequences city wells and west Williamsburg
stratigraphic section, as well as interpreted thickness of
QTpe units in the eastern part of the quadrangle. Note
that projections of subsurface units in cross-section
A-A’ indicate a cumulative thickness exceeding 500 m;
however, the lower contact of the Palomas Formation
beneath the modern Rio Grande is unconstrained by
well data. The cumulative thickness, and the thicknesses
of most individual units, of the western piedmont facies
increases toward the east, where the deepest part of the
Palomas basin is located (Fig. 22; Gilmer et al., 1986).
QUATERNARY HISTORY
(POST-PALOMAS FORMATION)
Deposition of the Palomas Formation ceased ~0.8 Ma
(Lozinsky and Hawley, 1986a, b; Mack et al., 1993, 1998,
2006; Mack and Leeder, 1999), after which the Rio Grande
and its tributaries began incising and gradually forming
the modern network of arroyos and river valleys. Valleymargin deposits are typified by inset stream terraces and,
in places, alluvial fans graded to those deposits. Valleybottom deposits include low-lying terraces adjacent to
modern stream courses. Topographically higher deposits
are typically middle to late Pleistocene in age. Exposed
valley-bottom deposits are considered Holocene on the
basis of radiocarbon dates discussed below, but at depth
these valley-bottom deposits are likely latest Pleistocene.
18
grade (Fig. 23). A component of very fine- to fine-grained
sand once occupying the terrace surfaces has been
deflated by southwesterly winds and deposited on the lee
sides of ridges 0.5-3 km east of the modern Rio Grande.
The remaining, non-eroded terrace deposits typically
comprise thin strath terraces (≤5 m). However, certain
deposits (Qtr1 and Qtr4) approach 10 m in thickness
and represent notable periods of river aggradation. Rio
Grande deposits are distinguished by an abundance
of exotic clasts, particularly quartzite. They also have
imbricated clasts that indicate southward paleocurrents
Figure 22. Complete Bouguer-anomaly gravity map of Palomas
basin and surrounding uplifts. Williamsburg quadrangle is outlined in
red. Note that deepest part of the basin coincides with a low gravity
anomaly located southwest of Las Palomas (LP) and the Barney Iorio
Fee #1 well (blue circle). Data from Kucks et al. (2001). Reduction
density = 2.67 gm/cc; sea level datum. Contour interval = 2 mGal.
Abbreviations for local communities (black dots) as in Figure 1.
In general, Pleistocene and Holocene deposits in the
Williamsburg quadrangle formed during periods of
climatic fluctuation related to glacial-interglacial cycles.
One model developed for the formation of stream terraces
in the southern Rio Grande rift proposes that terrace
formation occurs over three stages: (1) the Rio Grande
and the lower valleys of its tributaries incise during
full glacial conditions; (2) aggradation occurs during
the transition to interglacial intervals due to decreased
water to sediment ratios; and (3) stability ensues for the
Figure 23. Pleistocene Rio Grande terrace deposit (Qtr4). Rio
remainder of the interglacial interval (Gile et al., 1981).
Grande terrace deposits are distinguished from Palomas Formation
gravels by the presence of numerous exotic clasts, particularly
Terrace surfaces underlain by sand and gravel deposited quartzite. They also contain a higher proportion of cobbly gravel fills
by the Rio Grande represent former base levels of the than axial-fluvial facies of the Palomas Formation, and commonly
river, some of which are up to 40 m above its modern feature clast imbrication (arrows) suggesting paleoflow toward the
south. Tape is 2 m tall. SE¼ NE¼ sec. 31, T. 14 S., R. 4 W.
19
(Fig. 23; Appendix C) and contain lenses of well sorted,
quartzose sand. An ash collected from a thin exposure of
the highest exposed Rio Grande terrace deposit (Qtro)
along King Arroyo in NW¼ sec. 1, T. 15 S., R. 5 W. is
geochemically similar to the 640 ka Lava Creek B ash (N.
Dunbar, personal communication, 2015). Located 45 m
above modern grade, this deposit provides an approximate
mainstem Rio Grande incision rate of 70 m/Ma since the
mid-Pleistocene. However, this rate does not integrate
ages of younger, inset deposits that currently lack age
constraints (i.e. deposits of Qtr6, Qtr5, and Qtr4). Mack
et al. (2011) used radiocarbon dates from charcoal, bulk
organic matter, and shells to constrain deposition of
younger Rio Grande terraces at >12.4 ka (Qtr3), ~8-5.3
ka (Qtr2), and ~0.8-0.6 ka (Qtr1).
terraces, surface characteristics of these deposits imply
relative age, with stage II carbonate morphology observed
in soils capping older deposits (Qay) and bar-and-swale
topography better preserved in younger deposits that
mostly lack well developed soils (Qah). However, like
terrace deposits, surface erosion complicates the use of
soil development to infer deposit age. These inset deposits
are also associated with alluvial fans (units Qfah, Qfay)
that emanate from side gullies and ravines, commonly
interfingering with or prograding over deposits associated
with the mainstem stream (Fig. 24). Modern alluvium
(Qam) in ephemeral drainages is marked by sandy pebble
to cobble gravel forming pronounced bar-and-swale
topography.
Radiocarbon dates acquired in Cañada Honda, a
Rio Grande tributary, during the course of mapping
demonstrate that valley-bottom deposits span the
Holocene and extend into the latest Pleistocene (Table
3; Appendix D). Figure 25 shows radiocarbon sample
locations. Based on these ages, younger alluvium (Qayi)
pre-dating Qah represents backfilling of tributary valleys
~600 cal yr BP (sample WS-204, Table 3). Qfay was
aggrading at distal positions in the late Holocene, based
on the ~2500 cal yr BP age of sample WS-203 (Table
3). An interval 2.7-3.0 m below the surface (unit D of
Figure 24) of a more proximal alluvial fan deposit (Qfay),
overlying a paleosol with stage II carbonate morphology,
returned an age of ~11000 cal yr BP. The fan sediment
below the paleosol, which is finer grained than the
Holocene material above, is thus likely latest Pleistocene
in age. This fan almost certainly once interfingered with
unit Qay, based on similar geomorphic levels in the
valley, indicating a general Holocene-latest Pleistocene
age for both Qfay and associated Qay deposits. The age
of sample WS-204 is broadly similar to radiocarbon ages
obtained from Rio Grande terrace deposit Qtr1 (terrace
III dated by Mack et al., 2011).
Five correlated Palomas Creek terrace deposits (Qtp
units) are each 3-5 m thick and can be considered strath
terraces. The straths/treads of these terraces lie 7-47 m
above modern grade. Older terraces are marked by a
greater degree of surface varnish on clasts (up to 80%).
Surface erosion hampers the use of soil development to
correlate terraces, but where preserved the terrace soils
exhibit relatively strong calcium carbonate accumulation
(e.g. stage II or greater carbonate morphology), consistent
with long-stable surfaces (Gile et al., 1969; Birkland,
1999). Terrace deposits flanking Palomas Creek and
other Rio Grande tributaries west of the river are
distinguished by poor sorting and a high proportion of
volcanic clasts. Terrace deposits east of the Rio Grande
are likewise poorly sorted but are dominated by clasts
of Paleozoic carbonates and Proterozoic granite, and
lack cementation observed in QTpe strata. Correlations
between tributary and mainstem Rio Grande terraces are
confounded by the presence of thin fluvial gravels of the
Palomas Formation that have been exhumed in many
locations (especially in Kelly Canyon). Such intervals
were recognized in early mapping of the Palomas
basin (Harley, 1934), and resemble younger terrace
deposits because they have similar textures and appear
topographically inset. Furthermore, soil development
could be similar on exhumed Palomas Formation gravels
compared to post-0.8 Ma terrace surfaces at the same
geomorphic level. Adequate exposure in some localities
permits a relatively certain interpretation. However,
Qtp1b is clearly inset just beneath Qtr4 at the mouth of
Palomas Creek, demonstrating that tributary terraces
predate the Holocene.
STRUCTURAL GEOLOGY
The Williamsburg quadrangle features four major faults:
the Mud Springs, Williamsburg, Hot Springs, and Caballo
faults (Fig. 2). In addition, less extensive normal faults are
observed in the southwest and southeast corners of the
quadrangle.
The northernmost structure in the quadrangle is the
west- to southwest-down Mud Springs fault, which wraps
around the western foot of the Mud Springs Mountains
Younger valley-floor deposits lie well below terrace
deposits, flanking arroyos throughout the study area. Like
20
Figure 24. Younger alluvial fan (Qfay) deposit in Cañada Honda. Charcoal sample WS-202D was radiocarbon dated at 11200-10800 cal yr BP
(2σ calibration). Unit is characterized by poorly sorted pebbly sand and gravel with common stage I-II carbonate morphology in both surface
and buried soils. Surface soils may also feature illuviated clay (Bt horizons).
Table 3. Summary radiocarbon geochronology for Cañada Honda and Las Animas Creek study areas.
Sample #
Deposit
Material
UTM Na
UTM Ea
Conventional
2σ Calibrated Age Range
Age (14C yr BP1950) (cal yr BP1950)c
WS-202-D1
Qfay
charcoal
3665387
284572
9590 ± 30
11106-10763 (1.000)
WS-203
Qfay
charcoal
3665180
284659
2480 ± 30
2390-2385 (0.004), 27232432 (0.996)
WS-204
Qayi
charcoal
3665150
284689
540 ± 30
634-596 (0.308), 561-514
(0.692)
Coordinates given in UTM Zone 13S, NAD83.
a
Conservative error of ±30 14C yr BP1950 is given for all samples due to 1σ < ±30 14C yr BP1950 in each case.
b
2σ calibrated age ranges calculated as relative probability using Calib 7.1 (Stuiver and Reimer, 1993) and IntCal13 calibration curve of
Reimer et al. (2013).
c
21
107°19'W
tgw Qah Qfayr
Qam
107°18'W
fo
Qah
Qayr
Qfary
Qam
Qary
fo
fo
tfw
Qayi
Qay
Qfay
Qfar
Qayi
Qaym
Qary
Qah
Qahm
Qfar
fo
Qfay
fo
Qtr1b
Qah
Qfay
Qam
daf
d e
G r a n
Qfay
Qfay
Qam
Qfay
WS-202D (WCH)
fo
fo
Qamh
Qfay
WCH: 11200-10800 cal yr BP
Qfayi
MCH: 2800-2500 cal yr BP
Qfaym
Qfay
33°6'N
ECH: 630-580 cal yr BP
i o
Qfay
Qfaym
Qtr1a
Qfary
R
Qay
Qah
Qfay
tgw
Qayi
WS-203 (MCH)
WS-204 (ECH)
Qayi
Qtr1b
Qfayi
Qfayi
Qayi
fym
Qfay
fym
0.5
0
0.5 k m
Qtr1b
±
Figure 25. Surficial geologic map of Cañada Honda. Charcoal radiocarbon samples depicted by black circles. Unit designations from map;
other abbreviations as follows: r = subequal modern and historical alluvium, fo = older fan alluvium (Pleistocene, not discussed in text). Note
that Qayi grades into Rio Grande terrace Qtr1b, correlating to terrace III of Mack et al. (2011). Sample sites: west (WCH), middle (MCH),
and east (ECH) Cañada Honda.
(Kelley and Silver, 1952; Machette, 1987; Machette et
al., 1998). Its exact location has been inconsistently
mapped, with previous workers showing a discontinuous
structure differing in location by up to ~2 km (Maxwell
and Oakman, 1990; Foster, 2009). Although a lack of
geomorphic expression complicates mapping of the fault,
we have confirmed two definite southwest-down fault
strands northeast of the debris dam in lower Mud Springs
Canyon (Koning and Jochems, unpublished data). From
these exposures, it is evident that the Mud Springs fault
continues southeast under Holocene-latest Pleistocene
alluvium in lower Mud Springs Canyon. Northeastward
roll-over in Palomas Formation bedding, observed
adjacent to I-25 (SW¼ SW¼ sec. 6, T. 14 S., R. 4 W.),
can be reasonably attributed to deformation along this
structure.
fault is located south of Truth or Consequences and east
of the Rio Grande, where it forms fault scarps up to 6.4
m high (Machette et al., 1998). Surface ruptures along
a scarp of the Williamsburg fault in sec. 9, T. 14 S., R.
4 W. were dated at ~5-2 ka based on charcoal collected
from displaced colluvial beds; these ruptures average 2-3
m of vertical offset per event (Foley et al., 1988). The
southern segment of the Williamsburg fault juxtaposes
eastern piedmont facies of the Palomas Formation in
the footwall with younger fan gravel (middle to late
Pleistocene age) in the hanging wall. The southern
terminus of the Williamsburg fault is not well exposed
and thus its location is uncertain. Displacement may
progressively decrease along a cryptic strand towards
the south-southwest (shown as a concealed fault on the
geologic map). It is possible, however, that the southern
end of the fault may swing to the east, truncating the Hot
The northwest-striking, southwest-down Williamsburg Springs fault and intersecting the Caballo fault just east
22
of the quadrangle, as suggested by previous workers (e.g.,
Kelley and Silver, 1952; Seager and Mack, 2003). If the
latter scenario is true, the fault likely follows the course
of one of two arroyos at the southern end of Precambrian
strata exposed in the footwall of the Hot Springs fault, its
trace obscured by younger stream gravel and at least one
small fault antithetic to the Hot Springs structure.
We interpret that the southeast end of the Mud Springs
fault links with the northwest end of the Williamsburg
fault, probably via a 0.5 km step-over. This interpretation
is consistent with many previous studies that connect
the faults (e.g., Kelley and Silver, 1952; Foley et al., 1988;
Machette et al., 1998; Seager and Mack, 2003). We note
two additional stratigraphic observations that support the
existence of the fault under latest Pleistocene to Holocene
alluvium in the Williamsburg area: (1) correlation of lower
western piedmont deposits of the Palomas Formation
exposed in the footwall (i.e., topographic bluffs along the
northern quadrangle boundary) to buried hanging wall
strata at 240-600 ft depths (in Truth or Consequences city
wells 6, 7, and 8); and (2) paleontologic and radiometric
data indicating that exposed footwall strata are 5.3-4.8
Ma (Neohipparion eurystyle horse tooth in lower QTpa)
and topographically lower, exposed hanging wall strata
are 3.0-2.6 Ma (Williamsburg local fauna site; Morgan
and Lucas, 2012). Using these stratigraphic correlations,
estimated post 4.5 Ma vertical throw along the Mud
Springs fault on the quadrangle is 190-200 m.
Figure 26. Brecciated volcanic clasts in strongly silicified upper
Santa Fe Group strata (Tsus) forming sliver between two strands
of the Hot Springs fault. Individual clasts may be fractured; reddish
matrix likely derives hue from abundant clays. Hammer is 28 cm long.
Caballo fault forms the major range-bounding structure
of the Caballo uplift. The 400 m-long section that
crosses the extreme southeast corner of the Williamsburg
quadrangle has been called the Northern Caballo fault
(e.g., Machette, 1987; Foley et al., 1988; Seager and
Mack, 2003). Maximum displacement along this westdown structure is estimated at ~6.5 km based on gravity
data (Keller and Cordell, 1983; Gilmer et al., 1986) and
exposed thicknesses of Precambrian and Phanerozoic
packages in the Caballo Mountains (Seager and Mack,
2003). Most of the activity along the Northern Caballo
fault appears to predate the Palomas Formation. This
The west-down, north-striking Hot Springs fault dips up inference arises from the observation that the Northern
to 80° and places Precambrian rocks in its footwall against Caballo fault borders the deepest part of the Palomas
Mio-Pliocene basin-fill in its hanging wall. A ~1 km long basin (Fig. 22; Gilmer et al., 1986), yet intervals of the
splay of the fault, also downthrown toward the west, Palomas Formation (particularly units QTpwl and
exposes a sliver of strongly cemented, brecciated gravel QTpwm) thicken northward away from this structurally
that we correlate to the upper Santa Fe Formation (upper deep area.
Miocene) based on the presence of volcanic clasts (Fig.
26). The cumulative displacement along these structures Even if its slip rate has waned since the Miocene, the
is unknown in the Williamsburg quadrangle, but Mason Northern Caballo fault is still an active structure. Foley
(1976) estimated its displacement between 610 and 2740 and others (1988) estimated that the most recent surface
m in the northern Caballo Mountains, whereas Lozinsky rupture event of this fault occurred ~4-5 ka based on
(1986) assigned the fault a minimum displacement of soil development in faulted and unfaulted colluvium at a
1220 m at the wing dam of Elephant Butte Reservoir trenched scarp south of the quadrangle. They calculated
north of the quadrangle. The segment of the Hot Springs an average of 1.25-2 m of vertical offset per rupture event.
fault exposed in the quadrangle is clearly its southern
In addition to the major structures described above,
terminus, regardless of whether or not it is truncated by
several other normal faults are observed in the quadrangle.
the Williamsburg fault (see above), because exposures
A series of mostly west-down normal faults were mapped
of Proterozoic basement step ~800 m east between the
in the southeast corner of the quadrangle east of the
quadrangle and the footwall of the Caballo fault.
Rio Grande and west of the Northern Caballo fault. At
Together with the Hot Springs fault, the north-striking least one of these faults offsets deposits that are likely
23
middle-late Pleistocene in age. Apparent vertical throw
(i.e. displacement observed in outcrop) is typically <10
m on these faults, yet they may be traced as far as ~4.3
km or more. They are synthetic to the Northern Caballo
fault and may or may not be physically linked to this
master fault. In the southwest corner of the quadrangle, a
north-striking, west-down fault forms scarps that parallel
southerly orientated arroyos transverse to eastwardflowing drainages typical of the Palomas basin. This
structure belongs to the “unnamed faults west of Caballo
Reservoir” group of Machette et al. (1998), who assigned
it a maximum age of <750 ka based on offset of the
Cuchillo surface.
Iorio Fee #1 well. Only two saturated intervals within
Tsubf in the Barney Iorio well were reported in lithologic
logs completed in 1941. Although cementation is sparse
in this unit, its permeability is likely poor due to the
prevalence of fine-grained (especially clayey) beds, which
become more abundant to the south as the unit transitions
into a playa facies (Seager and Mack, 2003; Koning et
al., 2015). Therefore, we infer that Tsubf is probably a
poor to moderate aquifer in the northern quadrangle,
but becomes increasingly less permeable to the south and
transitions to an aquitard under the northern reaches of
Caballo Reservoir.
Most water-bearing units in the Palomas Formation
belong to the western-derived piedmont (QTpw) or axialfluvial facies (QTpa), as units of the eastern piedmont of
the Palomas Formation (QTpe and QTper) are generally
too cemented to host extensive aquifers. Additionally, unit
QTpef is likely too fine-grained to transmit appreciable
amounts of groundwater. The upper western piedmont
units (QTpwuc, QTpwu, and QTpwt) lie above the zone
of saturation throughout the quadrangle.
HYDROGEOLOGY
Despite the proximity of two of New Mexico’s largest
reservoirs, Elephant Butte and Caballo (first and fifth
largest, respectively), water for most practical purposes
in the Palomas basin is pumped from the ground.
Domestic, municipal, and stock wells typically penetrate
an artesian aquifer recharged by precipitation in the
Animas-Salado uplifts. To a lesser extent, there may
be recharge via flash flooding in ephemeral drainages
during the summer monsoons (Murray, 1959). Locally,
aquifers exist in gravelly pre-Palomas Formation Santa
Fe Group beds, moderately to coarse-grained Palomas
Formation strata, or Pleistocene to Holocene alluvium
(e.g., Murray, 1959; Cox and Reeder, 1962; Davie Jr. and
Spiegel, 1967). As discussed above and in Appendix A,
these units contain lithofacies with varying textures
and degrees of cementation that may either facilitate or
impede groundwater flow and infiltration. The following
discussion examines the aquifer-hosting potential of
basin-fill units in the Williamsburg quadrangle and relates
these inferences to previous hydrogeologic studies.
The aquifer-hosting potential of the middle and lower
western piedmont units may then be distinguished on the
basis of texture and continuity of coarser-grained beds
(Koning et al., 2015). Although mostly fine-grained, the
middle western piedmont (QTpwm) contains up to 20%
tongues of pebbly sand and pebble gravel with little to
no interstitial clay (Fig. 27). Dense vegetation growing
along such beds, observed near the Williamsburg I-25
interchange, suggest that some sand and gravel beds
in this unit are saturated. In addition, several wells in
Palomas Creek (including the Barney Iorio Fee #1 well)
penetrate intervals of QTpwm that host groundwater.
Thick fine-grained strata in this unit likely acts as
aquitards, and the degree of connectivity in the coarse
channel fills will influence their aquifer potential. A
Sparsely exposed in the quadrangle, upper Santa Fe deflection in the otherwise southeast-sloping water table
Group units (Tsu) predating the Palomas Formation surface, as interpreted by Murray (1959), near the mouth
(correlative to the Rincon Valley Formation to the of Palomas Creek suggests a truncation of QTpwm or
south) nevertheless hold important implications for QTpwl channel-fill connectivity below the eastern part
groundwater flow. Piedmont facies of the upper Santa of Palomas Creek. Seeps on the north side of Palomas
Fe Group (Tsupw) could transmit groundwater where Canyon west of I-25 may reflect such a pattern, although
they consist of laterally extensive channel fills with they could be emanating from QTpwu beds.
relatively low cementation. Such beds are estimated to
comprise ≤25% of the unit. In outcrop, upper Santa Fe The lower western piedmont (QTpwl) consists of
Group basin-floor facies (Tsubf) consist of very fine- relatively abundant coarse channel-fills interbedded
to medium-grained sand and clayey-silty sand with few with subordinate, light brown extra-channel deposits
(≤5%) pebbles. This unit includes mud and clay with composed of clay, silt, and very fine- to medium-grained
sparse interbeds of sand and fine gravel in the Barney sand. The channel-fills are composed of clast-supported,
24
sand with subordinate channel fills. Water was reported
from a 1 m interval in this unit in the Barney Iorio well
(540-543 ft depth).
In addition to coarse channel fills in QTpwl and in
QTpwm, sandy gravel and well sorted sand of the axialfluvial facies (QTpa) exhibit strong aquifer-hosting
potential, particularly west of the Rio Grande where
cementation is not commonly observed. Axial floodplain
mudstones and clay facies (QTpaf) may locally act as
aquitards, as could finer-grained facies in QTpwm. This
hydrogeologic relationship is observed in several wells
along Palomas Creek (data from NM Office of the State
Engineer, 2015).
Finally, Pleistocene and Holocene valley-floor units may
also locally host aquifers. Gravelly or sandy channelfills in historical alluvium (Qah) near the northwestern
corner of the quadrangle may be saturated in places along
Palomas Creek. Elsewhere, coarse valley-floor units can
be expected to transmit runoff, mostly during the summer
months of the monsoon season, to underlying Palomas
Formation aquifers. Alternatively, they may locally receive
groundwater discharge from buried Palomas Formation
aquifers (Davie Jr. and Spiegel, 1967).
ACKNOWLEDGEMENTS
Figure 27. Channel-fill gravel at top of middle western piedmont
facies (QTpwm). Though rare, such gravels are commonly extensive
over 50+ m and could form important, transmissive units for
groundwater because they lack clays and other fine material in their
matrices. Exposure in I-25 roadcut north of Las Palomas.
Mapping of the Williamsburg quadrangle was funded by
the STATEMAP program, which is jointly supported by
the U.S. Geological Survey and the New Mexico Bureau of
Geology and Mineral Resources (NMBGMR). We thank
J. Michael Timmons of NMBGMR for logistical support.
We are grateful for land access provided by Las Palomas
Land & Cattle Company (caretakers Andy Anderson,
Jonathan Beaty, and John Walker), Julie Durham, and
Twister Smith. Dr. Greg Mack and Dr. Peter Mozley
provided valuable field discussions on basin architecture
and pedogenic processes. Dr. Nelia Dunbar (NMBGMR)
analyzed the ash collected along King Arroyo. Finally,
Dr. John Hawley, NMBGMR emeritus, gave profound
insight into basin-fill stratigraphy and hydrogeology and
generously shared his many resources with us.
imbricated sandy gravel that lacks fine-grained matrix
sediment and is not generally cemented (although the
lowermost 1-2 m is well-cemented in exposures west of
I-25 along the northern quadrangle border). This unit
thickens toward the northern edge of the quadrangle
and its texture implies that it could be an ideal aquifer in
many locations. However, a 1941 lithologic log from the
Barney Iorio Fee #1 well did not report any water-bearing
intervals from QTpwl. Below this unit lies the transitional
base of the western Palomas Formation piedmont facies
(QTpwlt), observed only in cuttings of the Barney Iorio
Fee #1 well and Truth or Consequences city wells 7 and
8. There, QTpwlt consist of clay, silt, and fine-grained
25
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Machette, M.N., Personius, S.F., Kelson, K.I., Haller, Mack, G.H., Cole, D.R., and Treviño, L., 2000, The
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V.T., Lueth, V.W., Spielmann, J.A., and Krainer, K.
Camp Rice and Palomas Formations, southern Rio
eds., Geology of the Warm Springs Region: New
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377–392.
30
APPENDIX A
Detailed descriptions of lithologic units on the
Williamsburg 7.5’ quadrangle
UNIT DESCRIPTIONS
The units described below were mapped using aerial photography coupled with field checks, or by examining well
cuttings and comparing to existing lithologic descriptions in the case of subsurface units. Stereogrammetry software
(Stereo Analyst for ArcGIS 10.1, an ERDAS extension, version 11.0.6) permitted accurate placement of geologic
contacts. Grain sizes follow the Udden-Wentworth scale for clastic sediments (Udden, 1914; Wentworth, 1922) and
are based on field estimates. The term “clast(s)” refers to the grain size fraction greater than 2 mm in diameter.
Descriptions of bedding thickness follow Ingram (1954). Colors of sediment are based on visual comparison of
dry samples to Munsell Soil Color Charts (Munsell Color, 2009). Soil horizon designations and descriptive terms
follow those of Birkeland et al. (1991), Soil Survey Staff (1992), and Birkeland (1999). Stages of pedogenic calcium
carbonate morphology follow those of Gile et al. (1966) and Birkeland (1999). Description of sedimentary, igneous,
and metamorphic rocks was based on inspection using a hand lens.
Surface characteristics and relative landscape position were used in mapping middle Pleistocene to Holocene units.
Surface processes dependent on age (e.g. desert pavement development, clast varnish, calcium carbonate accumulation,
and eradication of original bar-and-swale topography) can be used to differentiate stream terrace, alluvial fan, and
valley floor deposits. Younger deposits are generally inset below older deposits. However, erosion may create a young
surface on top of an older deposit, so Quaternary deposits were field-checked to identify this relationship.
QUATERNARY EOLIAN UNITS
Qes
Eolian sand (Holocene) – Windblown sand occurring in pod-shaped coppice dunes atop flat ridges and
on their lee sides. Deposit is unconsolidated and often rippled. Matrix consists of pale to light yellowish
brown (10YR 6/3-4), very well sorted, subangular to rounded, very fine- to fine-grained quartzose sand.
Commonly vegetated with little or no soil development. Deposited by southerly to southwesterly winds on
the leeward (i.e. north) side of ridges (Kelley and Silver, 1952), with sediment derived from the floodplain of
the Rio Grande and deflated Palomas Formation deposits. Higher, non-vegetated dunes may be up to 2.3 m
(7.5 ft) thick; total thickness unknown but probably no more than 2.5 m (8.2 ft) in most locations. Locally
mapped as eolian mantle on older units (Qes/unit).
Qesc Eolian sand, slopewash, and hillslope colluvium, undivided (Holocene) – Mixed windblown sand and
pebble-cobble-boulder gravel typically found on lee sides of ridges east of the Rio Grande. Deposit is
unconsolidated and massive to rippled where dominated by eolian material. Clasts are poorly sorted and
angular to subangular. Commonly vegetated with little or no soil development. Maximum thickness likely
no more than 3 m (10 ft). Locally mapped as eolian-colluvial mantle on older units (Qesc/unit).
QUATERNARY HILLSLOPE UNITS
Qsc
Slopewash and colluvium, undivided (upper Pleistocene to Holocene) – Very pebbly sand found in thick beds
on bedrock highs and (less commonly) mantling Quaternary deposits. Deposit is very loosely consolidated
and massive. Clasts consist of angular to subrounded granules to pebbles. Matrix consists of light yellowish
brown (10YR 6/4), very well sorted silt to fine-grained sand. May be very weakly cemented by carbonate.
Commonly bioturbated by fine roots. Likely reworked by sheetflooding in most instances. Total thickness
typically 1.5-2 m (4.9-6.6 ft). Locally mapped as slopewash mantle on older units (Qsc/unit).
QUATERNARY VALLEY FLOOR UNITS
daf
Disturbed or artificial fill (modern) – Sand and gravel that has been moved by humans to form berms
and dams, or has been reworked/remobilized for construction of infrastructure or buildings.
Qaarg Active alluvium of the Rio Grande (present) – Sandy pebble-cobble gravel in the axial channel of the
Rio Grande, commonly in longitudinal or transverse bars. Clasts consist of poorly to moderately sorted,
32
subrounded to rounded pebbles and cobbles. Boulders may be present, transported from local tributaries
to the active channel during larger flood events. Clast lithologies are diverse, reflecting bedrock exposed
throughout Rio Grande catchment. Matrix consists of moderately to very well sorted, subrounded to
rounded, fine- to coarse-grained quartzose sand. Total thickness unknown but likely 1-5 m (3.3-16 ft).
Qam Modern alluvium (present to ~50 years old) – Sandy pebble to cobble gravel found in ephemeral channels
or adjacent low-lying surfaces, fluvially reworked by modern flow events. Unconsolidated and commonly
imbricated. Clasts are poorly to very poorly sorted, angular to subrounded, and consist of 65% pebbles,
30% cobbles, and 5% boulders. Clasts are dominated by granite, metamorphic lithologies, and Paleozoic
carbonates where streams exit the footwall of the Caballo fault system east of the Rio Grande. To the west,
clasts are dominated by volcanic lithologies derived from the Sierra Cuchillo and Black Range (including
those reworked from the Palomas Formation). Matrix consists of brown to light brown (7.5YR 5-6/3)
to dark yellowish brown or light brownish gray (10YR 4/4-6/2), poorly to moderately sorted, angular to
subrounded, fine- to very coarse-grained sand. Pronounced bar-and-swale topography exhibits up to 60 cm
(24 in) of relief. Sparsely to non-vegetated with no soil development. Total thickness is unknown but likely
1-3 m (3.3-9.8 ft).
Qamh Modern and historical alluvium, undivided (present to ~600 years old) – Modern alluvium (Qam) and
subordinate historical alluvium (Qah). See detailed descriptions of each individual unit.
Qamy Modern and younger alluvium, undivided (present to lower Holocene) – Modern alluvium (Qam) and
subordinate younger alluvium (Qay). See detailed descriptions of each individual unit.
Qah
Historical alluvium (~50 to ~600 years old) – Pebbly sand and sandy pebble gravel in very thin to thin (less
commonly medium to thick), tabular to lenticular beds. Deposit is loosely consolidated, clast- to matrixsupported, and massive to horizontal-planar laminated or imbricated. Clasts are poorly to moderately sorted,
angular to rounded, and consist of 80-90% pebbles, 10-20% cobbles, and 0-5% small boulders. Clasts are
dominated by granite, metamorphic lithologies, and Paleozoic carbonates where streams exit the footwall
of the Caballo fault system east of the Rio Grande. To the west, clasts are dominated by volcanic lithologies
derived from the Sierra Cuchillo and Black Range (including those reworked from the Palomas Formation).
Matrix consists of brown (7.5YR 6/4) to grayish or yellowish brown (10YR 5/2-4), poorly to well sorted,
angular to subrounded, fine- to very coarse-grained sand and silty sand. Very weak carbonate cement may
be present. Surface exhibits subdued bar-and-swale topography and channel forms with 10-40 cm (6-8
in) of relief. Moderately vegetated with little or no soil development (marked by weak ped development
yet obvious sedimentary fabric) and commonly mantled by 20-30 cm (8-16 in) of silty fine sand related to
slopewash or overbank deposition. Bioturbation by fine to very coarse roots or burrows is common. A
radiocarbon date from Cañada Honda returned an age of 630-515 cal yr BP. Tread is 0.4-1.3 m (1.3-4.3 ft)
above modern grade. Base not observed in thickest deposits; possibly up to 3 m (9.8 ft) maximum thickness.
Qahm Historical and modern alluvium, undivided (present to ~600 years old) – Historical alluvium (Qah) and
subordinate modern alluvium (Qam). See detailed descriptions of each individual unit.
Qahy Historical and younger alluvium, undivided (~50 years old to lower Holocene) – Historical alluvium (Qah)
and subordinate younger alluvium (Qay). See detailed descriptions of each individual unit.
Qar
Recent (historical + modern) alluvium (present to ~600 years old) – Historical alluvium (Qah) and modern
alluvium (Qam) in approximately equal proportions. See detailed descriptions of each individual unit.
Qary Recent (historical + modern) and younger alluvium, undivided (present to lower Holocene) – Recent
alluvium (Qah + Qam) and subordinate younger alluvium (Qay). See detailed descriptions of each individual
unit.
Qay Younger alluvium (Holocene) – Sand and pebbly sand to sandy pebble-cobble gravel. Finer sediment
dominates in low-gradient, low-order drainages and consists of very thin to thick, tabular (minor lenticular)
beds of brown to light brown (7.5YR 5/2-4; 6/3-4; 10YR 5/3) to light brownish gray (10YR 6/2), mostly
massive (locally horizontal-planar laminated), very fine- to medium-grained sand or clayey-silty, very fineto medium-grained sand. This finer sediment generally contains minor coarse- to very coarse-grained sand
and 1-20% scattered pebbles, with 1-25% very thin to thin lenses of sandy pebble gravel or pebbly sand
(locally 1-10% cobbles). In the finer sediment, cumulic soil development is common and characterized
by weakly to strongly developed, medium to coarse, subangular blocky peds as well as local minor clay
33
illuviation and stage I carbonate morphology. Coarser sediment dominates in steep canyons incised
relatively deeply in the Palomas Formation. These deposits consist of sandy gravel in very thin, tabular to
lenticular beds. In larger, deeply incised drainages this coarse sediment is interbedded with finer sediment
like that described above. Gravels are typically clast-supported with minor matrix-supported debris flow
beds. Imbrication is common in clast-supported beds and sandy or pebbly beds may be cross-stratified
(foresets up to 10 cm thick). Gravel consist of poorly to moderately sorted, subangular to rounded (mostly
subrounded) pebbles and subordinate cobbles whose compositions reflect lithologies exposed upstream of
the deposit (see descriptions of Qam and Qah clast lithologies). Matrix consists of poorly to moderately well
sorted, subangular to subrounded, medium- to very coarse-grained sand. Sand in coarser deposits is brown
to light brown (7.5YR 5/2-6/3), dark brown to brown (10YR 3-5/3), or dark yellowish brown to yellowish
brown (10YR 4-5/4). Both coarse and fine varieties exhibit little to no pedogenic carbonate development
on the surface, but buried calcic horizons are relatively common (stage I to II carbonate morphology).
Surfaces locally show signs of erosion. Where erosion is minimal, stage I to II carbonate morphologies in
the topsoil are typical, with upper parts locally accompanied by illuviated clay (i.e. Btk horizons overlying
a Bk horizon). The calcic or illuviated clay horizons are locally overlain by 10-15 cm (4-6 in) thick, brown
(10YR 4-5/3) A horizons marked by accumulation of organic matter and fine sediment deposited by eolian
or slopewash processes. A radiocarbon date from Cañada Honda for the lowest part of correlative Qfay
deposits returned an age of ~11000 cal yr BP, but upper age is likely middle to late Holocene. Weakly to
moderately consolidated and typically 2-5 m (6.6-16.4 ft) thick. Locally divided into an inset deposit:
Qayi Younger inset alluvium (upper Holocene) – Pebbly sand, sandy gravel, and sand in very thin to
medium, lenticular to tabular beds. Looser than Qayi deposits and lacks buried soils. Gravel are
clast-supported, commonly imbricated, and poorly sorted. Sand is grayish brown to pale brown
(10YR 5/2-6/3), poorly to moderately sorted, subangular to subrounded, and very fine- to very
coarse-grained. Locally silty (1-15% silt). Soil is marked by weak accumulation of calcium carbonate
(stage I carbonate morphology), with <30% thin films of calcium carbonate mostly on undersides
of clasts. A radiocarbon date from Cañada Honda returned an age of 630-580 cal yr BP. Up to 4.5
m (15 ft) thick.
Qaym Younger and modern alluvium, undivided (present to lower Holocene) – Younger alluvium (Qay) and
subordinate modern alluvium (Qam). See detailed descriptions of each individual unit.
Qayh Younger and historical alluvium, undivided (~50 years old to lower Holocene) – Younger alluvium (Qay)
and subordinate historical alluvium (Qah). See detailed descriptions of each individual unit.
Qayr Younger and recent (historical + modern) alluvium, undivided (present to lower Holocene) – Younger
alluvium (Qay) and subordinate recent alluvium (Qah + Qam). See detailed descriptions of each individual
unit.
QUATERNARY TERRACE DEPOSITS
Terrace deposits of the Rio Grande
Qtr
Rio Grande terrace deposits, undivided (middle Pleistocene to Holocene) – Pebble-cobble gravel with sand
lenses in mostly thick, tabular to lenticular beds. Mostly unconsolidated, clast-supported, and imbricated to
trough cross-stratified. Clasts consist of poorly to moderately sorted, subrounded to well rounded pebbles,
cobbles, and small boulders of porphyritic volcanic rocks, Cretaceous sandstone, Paleozoic carbonate and
jasperoid, quartzite, and granite. Clast undersides occasionally to commonly coated by carbonate. Matrix
consists of silty, fine-to coarse-grained sand containing over 55% rounded quartz grains. Deposit may be
capped by pedogenic carbonate or eolian silt to fine-grained sand. Locally subdivided into 6-7 deposits
based on landscape position:
Qtr1 First or lowest Rio Grande terrace deposit (~260 to ~800 years old) – Weakly to moderately calcareous
and thin- to thick-bedded with occasional ripple cross-stratification (foresets up to 15 cm thick) of
sandier layers. Contains very few boulders. Brown to pale brown (10YR 5-6/3) matrix. Commonly
34
bioturbated by sedges and salt cedar. Locally subdivided into two deposits, Qtr1a and Qtr1b, with
tread heights <3 and<5 m (<9.8 and <16.4 ft) above modern grade, respectively. Correlative to
terrace deposits IV and III of Mack et al. (2011), respectively. The former was dated at < ~0.3 ka
based on air photos and radiocarbon ages for charcoal and bivalve shells, the latter at <0.6-0.8 ka
based on radiocarbon ages for microcrystalline calcite filaments in capping soil. Overall, deposits
lack strong soil development. Tread height ≤3 m (10 ft) above modern grade. 2.8 to perhaps 7 m
(9-23 ft) thick.
Qtr2 Second or middle-lower Rio Grande terrace deposit (~5,300 to ~8,000 years old) – Pebbly to clayey
sand with common calcic horizons. Correlative to terrace deposit II of Mack et al. (2011) that was
radiocarbon-dated at <5.3-8 ka. Tread height 3-6 m (10-20 ft) above modern grade. Approximately
2-3 (6.6-10 ft) thick.
Qtr3 Third or middle Rio Grande terrace deposit (upper Pleistocene to lower Holocene) – Well imbricated
with occasional trough cross-stratification. Contains very few boulders. Pale brown (10YR 6/3)
matrix. Varnish on 10-12% of clasts at surface. Stage I+ carbonate morphology in upper 80 cm (32
in) indicated by carbonate coats and/or rinds on up to 90% of clasts and common carbonate cement.
Capped by up to 40 cm (16 in) of Qes. Perhaps correlative to terrace deposit I of Mack et al. (2011);
calcic nodules from a mature soil capping this deposit were radiocarbon-dated at <12.4 ka. Tread
height 5-8 m (16-26 ft) above modern grade. 1.5-3 m (5-10 ft) thick.
Qtr4 Fourth or middle-upper Rio Grande terrace deposit (upper Pleistocene) – Medium- to thick-bedded
and well imbricated. Contains up to 15% boulders with ~30% flaggy clasts. Light yellowish brown
(10YR 6/4) matrix. Sandy lenses composed of 85-90% pebbles are common and up to 25 cm (10 in)
thick. Deposit capped by 35 cm (14 in) thick stage II+ carbonate horizon in which 90% of clasts
have carbonate rinds up to 1.5 mm thick. Tread height 18-24 m (59-79 ft) above modern grade. 3.6-9
m (12-30 ft) thick.
Qtr5 Fifth or upper Rio Grande terrace deposit (middle to upper Pleistocene?) – Mostly unconsolidated,
non- to moderately calcareous, broadly lenticular, and well imbricated to vaguely trough crossstratified. Contains up to 5% boulders. Light brownish gray to pale brown (10YR 6/2-3) matrix.
Stage II+ carbonate morphology in upper 70-90 cm (28-35 in) indicated by carbonate coats and/or
rinds on all clasts and common carbonate cement. May be mantled by 0.5-2 m (1.6-6.6 ft) of Qes or
Qesc. One deposit near King Arroyo contains ash geochemically correlated to 640 ka Lava Creek B
tephra (N. Dunbar, personal communication, 2015). Tread height 24-42 m (79-98 ft) above modern
grade. 2-6.8 m (6.6-22 ft) thick.
Qtr6 Oldest or highest Rio Grande terrace deposit (middle Pleistocene) – High exposures of rounded
gravel containing exotic clasts such as quartzite. Represents thin remainder of coarse channel load
of the ancestral Rio Grande. Tread height >45 m (118-138 ft) above modern grade. Maximum
thickness 3 m (10 ft).
Terrace deposits of Palomas Creek
Qtp
Terrace deposits of Palomas Creek, undivided (middle to upper Pleistocene) – Sandy pebble-cobble gravel
in thin to very thick, tabular to lenticular beds. Unconsolidated and very weakly to moderately calcareous.
Clasts consist of poor to moderately sorted, subrounded to well rounded pebbles and cobbles of Tertiary
volcanic and Paleozoic carbonate lithologies sourced from the Salado Mountains and eastern Black Range.
Older terrace deposits may feature more varnished clasts at surface. Deposits underlie inset surfaces along
Palomas Creek; most deposits underlie relatively thin (up to ~5-7 m thick) strath terraces, but thicker fills
may be present in places. Locally subdivided into 4-5 deposits based on landscape position:
Qtp1 First or lowest terrace deposit of Palomas Creek (upper Pleistocene) – Sandy gravel in medium
to thick beds. Clasts include subequal proportions of pebbles and cobbles with 10-15% boulders.
Locally subdivided into Qtp1a and Qtp1b with tread heights 7-16 m (23-53 ft) and 16-18 m (53-59
ft) above modern grade, respectively. 2-4 m (6.6-13 ft) thick.
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Qtp2 Second or middle-lower terrace deposit of Palomas Creek (upper Pleistocene) – Weakly calcareous
and thick- to very thick-bedded. Brown (7.5-10YR 4/3) matrix. Contains no more than 3% boulders.
Varnish on 20-30% of clasts at surface. Local Fe-oxidation occurs on clast undersides in ~30 cm (12
in) thick zones. Few preserved soils (likely eroded). Well preserved along most of Palomas Creek in
quadrangle. Tread height 24-31 m (80-102 ft) above modern grade. 2-6 m (6.6-20 ft) thick.
Qtp3 Third or middle terrace deposit of Palomas Creek (middle Pleistocene?) – Very weakly calcareous
and thin- to thick-bedded. Brown (10YR 5/3) matrix. Imbricated to weakly planar cross-stratified
with fine to medium pebbles concentrated along bases of individual foresets. Clast lithologies
include up to 35% Kneeling Nun tuff and aphanitic rhyolite. Varnish on up to 50% of clasts at
surface. Contains more feldspar grains (up to 70%) than other terrace deposits. Tread height 33-40
m (108-131 ft) above modern grade. 1.4-3 m (4.6-10 ft) thick.
Qtp4 Fourth or upper terrace deposit of Palomas Creek (middle Pleistocene) – Sandy pebble-cobble
gravel. Brown (7.5YR 4-5/3) matrix. Varnish on up to 80% of clasts at surface. Soil development
uncommon (likely eroded). Moderately dissected in places. Tread height 40-47 m (131-154 ft) above
modern grade. 5-8 m (16-26 ft) thick.
Terrace deposits of ephemeral drainages
Qtge Terrace deposits of ephemeral drainages east of the Rio Grande (middle to upper Pleistocene) – Sandy
pebble-cobble gravel in medium to thick, tabular to lenticular beds. Unconsolidated, commonly imbricated,
and occasionally planar cross-stratified (foresets up to 25 cm thick). Clasts consist of poorly to moderately
well sorted, subangular to rounded pebbles (70-90%), cobbles (10-20%), and subordinate boulders (5-10%)
derived from the Palomas Gap area. Clasts are composed of Paleozoic sedimentary and Precambrian igneous
and metamorphic lithologies. Gravel are better sorted near the top of the deposit and 18-20% of clasts are
varnished at the surface. Matrix consists of light grayish brown (10YR 6/2), poorly to moderately sorted,
subrounded, very fine- to medium-grained sand that is commonly arkosic (>50% K-spar). May exhibit stage
I+ to II carbonate morphology. Tread height up to 19 m (62 ft) above grade. Typically a thin strath terrace
deposit that is 1-3 m (3.3-10 ft) thick.
Qtgw Terrace deposits of ephemeral drainages west of the Rio Grande (middle to upper Pleistocene) – Sandy
pebble to pebble-cobble-boulder gravel in thin to thick, tabular to lenticular beds. Local sandy sediment
in medium, lenticular to tabular beds. Unconsolidated to very weakly carbonate cemented and massive to
imbricated. Sandy pebble beds may be planar or trough cross-stratified. Clasts are very poorly to poorly
sorted, subangular to rounded, and consist of 50-85% pebbles, 15-50% cobbles, and 3-10% boulders of
flow-banded rhyolite (≤30%), vesicular or dense basalt (≤20%), andesite or basaltic andesite, and perhaps
Paleozoic sedimentary lithologies. Occasional open-framework lenses of pebbles and cobbles are up to
60 cm (24 in) thick. Matrix consists of reddish brown (5YR 4/4) to light brown (7.5YR 6/3), poorly to
moderately sorted, angular to rounded, very fine- to coarse-grained sand composed of 30-60% feldspar,
30-50% lithic, and 10-30% quartz grains with up to 15% reddish clay films. Rare sand lenses are under
25 cm (10 in) thick and consist of planar cross-stratified sand with <15% granules. Deposit exhibits stage
I-II carbonate morphology and is capped by A and Bw to Bt horizons up to 50 cm (20 in) thick in places.
Typically comprises thin strath terrace deposits that underlie treads 6-20 m (20-66 ft) above modern grade.
1-2 m (3.3-6.6 ft) thick.
QUATERNARY ALLUVIAL FAN UNITS
Qfam Modern alluvial fan deposits (present to ~50 years old) – Unconsolidated pebbly sand and sandy pebblecobble gravel in channels and low-lying bars of small fans, subjected to fluvial reworking in modern times.
Sand consists of light yellowish brown to pale brown (10YR 6/4 to 7/2-3), moderately sorted, subangular to
rounded, very fine to medium grains of 50-60% quartz, 30-40% feldspar, and 5-15% lithic grains. Sand is
locally ripple laminated. Gravel clasts are poorly to moderately sorted, subangular to rounded, and consist
of 80-90% pebbles and 10-20% cobbles. Both sand and gravel-dominated units form bars, but gravel bars
form greater local relief (up to 0.8 m). Maximum thickness approximately 2.5 m (8 ft).
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QfamhModern and historical alluvial fan deposits, undivided (present to ~600 years old) – Modern alluvium
(Qfam) and subordinate historical alluvium (Qfah) deposited on alluvial fans. See detailed descriptions of
each individual unit.
QfamyModern and younger alluvial fan deposits, undivided (present to lower Holocene) – Modern alluvium
(Qfam) and subordinate younger alluvium (Qfay) deposited on alluvial fans. See detailed descriptions of
each individual unit.
Qfah Historical alluvial fan deposits (~50 to ~600 years old) – Sandy pebble-cobble gravel in very thin to very
thick, tabular beds. Unconsolidated, moderately to strongly calcareous, clast- to matrix-supported, and
massive/poorly stratified to weakly imbricated. Clasts consist of poorly sorted, subangular to rounded
pebbles (60-80%), cobbles (10-40%), and small boulders (0-10%) Matrix consists of very pale brown (10YR
7/3), poorly to moderately sorted, subangular to rounded, fine- to medium-grained sand composed of 4060% lithic, 20-40% quartz, and 10-20% feldspar grains. Clasts are covered by up to 70% by carbonate coats,
indicating stage I carbonate morphology. Moderately bioturbated by medium to coarse roots and burrows
up to 6 cm (2.4 in) in diameter. Surface is non-varnished and has 10-20 cm (4-8 in) of bar-and-swale relief.
Deposit surface is graded to a surface 1.5 m (5 ft) above modern grade. 1.2-2 m (3.9-6.6 ft) thick.
QfahmHistorical and modern alluvial fan deposits, undivided (present to ~600 years old) – Historical alluvium
(Qfah) and subordinate modern alluvium (Qfam) deposited on alluvial fans. See detailed descriptions of
each individual unit.
Qfahy Historical and younger alluvial fan deposits, undivided (~50 years old to lower Holocene) – Historical
alluvium (Qfah) and subordinate younger alluvium (Qfay) deposited on alluvial fans. See detailed descriptions
of each individual unit.
Qfar Recent (historical + modern) alluvial fan deposits (present to ~600 years old) – Historical (Qfah) and modern
(Qfam) fan alluvium in approximately equal proportions. See detailed descriptions of each individual unit.
Qfary Recent (historical + modern) and younger alluvial fan deposits, undivided (present to lower Holocene) –
Recent fan alluvium (Qfah + Qfam) and subordinate younger fan alluvium (Qfay). See detailed descriptions
of each individual unit.
Qfay Younger alluvial fan deposits (lower to upper Holocene) – Pebbly sand to sandy gravel in very thin to
medium, tabular to lenticular beds. Overall, bedding is convex-up transverse to the fan, centered on fan
axis. Unconsolidated to weakly carbonate-cemented, mostly clast-supported, and massive to locally planar
cross-stratified (up to 15% of a given exposure). Clasts are poorly to moderately sorted, subrounded, and
consist of ≤95% pebbles, ≤30% cobbles, and ≤5% boulders. Clasts are dominated by granite, metamorphic
lithologies, and Paleozoic carbonates where streams exit the footwall of the Caballo fault system east of
the Rio Grande. To the west, clasts are dominated by volcanic lithologies derived from the Sierra Cuchillo
and Black Range (including those reworked from the Palomas Formation). Matrix consists of brown to
light brown (7.5YR 4-6/3-4; 10YR 4-5/3) to pinkish gray (7.5YR 6/2) to grayish or yellowish brown (10YR
5/2-4), poorly to moderately well sorted, subrounded, very fine- to very coarse-grained sand that is locally
silty. Mostly deposited by stream-flow processes, but 5-25% of outcrops are matrix-supported debris flows
or hyperconcentrated flows that are in either: 1) pebbly, internally massive beds; or 2) thin to medium,
lenticular beds with pebbles and cobbles in a relatively fine matrix. Sandy sediment is typically bioturbated
by medium to very coarse roots. Buried soils are common and marked by accumulation of calcium carbonate
(stage I to II carbonate morphologies). Lowest strata is redder and finer-grained (i.e., more clay and fewer
cobbles), and may be overprinted by a paleosol marked by illuviated clay. Unit fines in distal part, where it
interfingers with and grades into units Qay or Qayi. Deposit is commonly capped by 10 cm (4 in) thick A
horizons exhibiting ped development, finer textures, and slight accumulation of organic matter. Underlying
the A horizon are: 1) Bt horizons where clasts and peds are covered by clay films (only locally observed);
and 2) common calcic horizons with stage I to I+ carbonate morphology that are 10-80 cm (4-32 in) thick.
Surface commonly shows evidence of erosion, such as gullies up to 2 m (6.6 ft) deep or an erosional lag of
coarse pebbles to cobbles, and in these areas lacks notable soil development. On higher, relatively stable
surfaces the clasts are weakly varnished and undersides are reddened. Less than 20 cm (8 in) of bar-andswale topographic relief, which is imperceptible on many of the higher surfaces. A radiocarbon date from
Cañada Honda returned an age of ~11200-10830 cal yr BP. Maximum thickness ~4 m (13.1 ft). Locally
subdivided into an inset unit:
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Qfayi Younger alluvial fan deposits graded to Qayi (upper Holocene) – Deposit is as described for Qfay,
with weak surface clast varnish and soil development. Perhaps less eroded and featuring greater (up
to 20 cm) of bar-and-swale topographic relief than Qfay. A radiocarbon date from Cañada Honda
returned an age of 2720-2385 cal yr BP.
QfaymYounger and modern alluvial fan deposits, undivided (present to lower Holocene) – Younger alluvium
(Qfay) and subordinate modern alluvium (Qfam) deposited on alluvial fans. See detailed descriptions of
each individual unit.
Qfayh Younger and historical alluvial fan deposits, undivided (~50 years old to lower Holocene) – Younger alluvium
(Qfay) and subordinate historical alluvium (Qfah) deposited on alluvial fans. See detailed descriptions of
each individual unit.
Qfayr Younger and recent (historical + modern) alluvial fan deposits, undivided (present to lower Holocene) –
Younger fan alluvium (Qfay) and subordinate recent fan alluvium (Qfah + Qfam). See detailed descriptions
of each individual unit.
Qfao Older alluvial fan deposits (middle to upper Pleistocene) – Alluvial fan deposits underlying surfaces graded
to higher positions above modern grade than those of Qfay. Deposit consists of sandy pebble-cobble gravel
in thin to thick, tabular to lenticular beds. Unconsolidated to somewhat carbonate-cemented and massive to
weakly imbricated. Clasts are poorly sorted, subangular to subrounded, and consist of 55-75% pebbles, 3040% cobbles, and 0-10% boulders of lithologies reflecting local source areas. Generally features moderate
to strong varnish on clasts at surface, which have reddened undersides (more varnished than Qfay surface,
except where severely eroded). Matrix consists of mostly brown to light brown (7.5YR-10YR 4-6/3-4),
poorly to moderately sorted, subangular to subrounded, very fine- to very coarse-grained sand composed
of 60-70% lithic (volcanic+carbonate), 30-40% feldspar, and 5-10% quartz grains. Surface generally shows
signs of erosion. Maximum thickness approximately 3-4 m (10-13 ft). Subdivided into 4 deposits along
Palomas Creek:
Qf1
Deposits of alluvial fans graded to lowest terraces (upper Pleistocene) – Light yellowish brown (10YR
6/4) matrix. Unconsolidated but strongly calcareous, tabular, and massive to weakly imbricated.
Features stage I carbonate morphology in upper part. Generally over 2 m (6.6 ft) thick.
Qf2
Deposits of alluvial fans graded to middle-lower terraces (upper Pleistocene) – Brown (7.5YR 5/4)
matrix. Unconsolidated, calcareous, tabular to lenticular, and weakly imbricated. Varnish on 60-70%
of clasts at surface. Maximum thickness 4 m (13 ft).
Qf3
Deposits of alluvial fans graded to middle terraces (middle Pleistocene?) – Pinkish gray (7.5YR
6/2) matrix. Somewhat calcareous, tabular, and massive to weakly imbricated. Features stage I+
carbonate morphology in upper part, indicated by carbonate coatings on up to 50% of clasts. Feoxide staining observed on up to 10% of clasts. 2-3 m (6.6-10 ft) thick.
Qf4
Deposits of alluvial fans graded to upper terraces (middle Pleistocene) – High, poorly preserved
deposit observed near western quadrangle boundary, south of Palomas Creek. Not described in
detail.
Qtfw Fan terrace deposits graded to terraces in Cañada Honda (middle to upper Pleistocene) – Sandy fan gravel
interbedded with Qtgw terrace surfaces in Cañada Honda. Likely correlative with Qf2 or Qf3 deposits.
Perhaps up to 3.5 m (11.5 ft) thick.
Qfe
Older alluvial fan deposits east of the Rio Grande (middle to upper Pleistocene) – Sandy pebble-cobble
gravel in thick, tabular to broadly lenticular beds underlying surfaces graded to or below Qtr deposits east of
the Rio Grande. Weakly to moderately consolidated, moderately to strongly calcareous, clast-supported, and
massive to moderately well imbricated. Clasts are very poorly to poorly sorted, subangular to subrounded,
and consist of 50-70% pebbles and 30-50% cobbles of Precambrian granite and metamorphic lithologies
(50%), Paleozoic carbonates (45%), and exotic volcanic and quartzite clasts reworked from QTpa (5%). Matrix
consists of light yellowish brown (10YR 5-6/4), poorly sorted, mostly subrounded, fine- to medium-grained
sand composed of 35% quartz, 35% lithic (carbonate+granite), and 30% feldspar (K-spar>plagioclase)
grains. Occasional (15%) matrix-supported intervals are massive and composed of material similar to the
gravel matrix. Commonly contains gastropods in sandier beds. Correlates to alluvial fan deposits in unit
38
Qvo of Seager and Mack (2005). >18 m (59 ft) thick.
QUATERNARY-TERTIARY BASIN-FILL UNITS
QTp Palomas Formation (lowermost Pliocene to lower Pleistocene) – Sand, silt, gravel, and clay deposited
by coalesced fan complexes and the ancestral Rio Grande in the Palomas and Engle basins. Where not
significantly eroded, the surface soil capping the youngest Palomas Formation is marked by a petrocalcic
horizon that is 1-2 m (3.3-6.6 ft) thick and generally exhibits stage IV carbonate morphology. More
information on this horizon and the constructional surface developed on the Palomas Formation, the
Cuchillo surface, can be found in McCraw and Love (2012). Type sections of the Palomas Formation in
the Williamsburg quadrangle are found at NW¼ NW¼ sec. 30 and NE¼ SW ¼ sec. 33, T. 14 S., R. 4 W.
Initially thought to be 100-131 m (328-439 ft) thick (Lozinsky and Hawley, 1986a), our work suggests a
total thickness for the Palomas Formation of 240-275 m (800-900 ft) in this quadrangle. Subdivided into 12
units:
QTpa Axial facies of the Palomas Formation – Pebbly to silty sand that is horizontal-planar laminated
to planar or trough cross-stratified; also in laminated to very thick, lenticular beds. Subordinate
facies are sandy pebble-cobble gravel in medium to thick, lenticular to broadly lenticular beds or
cross-stratified (up to 1 m thick). This coarse facies dominates the lower 20-25 m (66-82 ft) of
the unit, as exposed north of Truth or Consequences. Locally reverse graded. Unconsolidated to
weakly carbonate- or silica-cemented. Fluting occurs in select beds. Clasts consist of moderately to
moderately well sorted, subangular to subrounded pebbles and cobbles of basalt, rhyolitic ash-flow
tuff, andesite, dacite, quartzite, granite, chert, and carbonate and clastic sedimentary strata. Matrix
consists of light brown (7.5YR 6/4) to pale brown (10YR 6/3) or light gray (10YR 7/2), moderately
to very well sorted, subrounded to rounded, very fine- to coarse-grained sand comprised of 65-85%
quartz, 10-25% feldspar, and 5-10% lithic grains. Yellowish tan to very pale green clay occurs in
thin lenses in sandy deposits. Deposit commonly features nodular or ellipsoidal concretions of ironoxide minerals. The former may be up to 30 cm (12 in) across, the latter up to 8 cm (2.4 in) across.
Sandy beds typically represent channel margin or sandbar deposits of the ancestral Rio Grande. Silty
to clayey beds are floodplain deposits, while gravel beds are intra-channel facies. Fossils recovered
from this unit include gastropods and shells less than 1.5 cm (0.6 in) across, as well as freshwater
species represented by salamander (Amystoma sp.), frog (Rana sp.), and a medium-sized rodent (e.g. a
packrat). A tooth of the late Hemphillian horse Neohipparion eurystyle, collected from spoil piles just
north of the quadrangle, suggests an age of 5.3-4.9 Ma for the earliest ancestral Rio Grande gravels
(G. Morgan, personal communication, 2015). 40-115 m (130-380 ft) in a 3-5 km (1.9-3.1 mi) belt
centered on the modern Rio Grande valley in the Williamsburg quadrangle. Locally divided into 2
subfacies:
QTpacCoarse-grained axial facies of the Palomas Formation – Sandy pebble-cobble and pebble-cobbleboulder gravel/conglomerate in medium to very thick, tabular to lenticular beds deposited in
laterally extensive channel-fill complexes. Weakly to strongly consolidated, moderately calcareous,
and massive to well imbricated and/or planar cross-stratified (foresets up to 50 cm thick). Lateral
accretion sets are occasionally observed. Strongly indurated exposures preserve flute casts in rare
instances. Clasts are very poorly to moderately sorted, subangular to rounded, and consist of
40-50% pebbles, 30-50% cobbles, and 0-20% boulders of diverse lithologies including Tertiary
volcanics, Cretaceous sandstone, Paleozoic carbonates, and quartzite. Limestone, sandstone, and
siltstone constitute a greater proportion (up to 80% total) of clasts in basal beds; volcanics and
quartzite increase up-section. Imbricated gravel beds yield paleocurrent directions averaging SSE,
but in the lowest part paleoflow is to the SSW. Matrix consists of light yellowish brown to very
pale brown (10YR 6/4-7/3), poorly sorted, subrounded to rounded, fine- to coarse-grained sand
composed of 40-65% quartz, 25-35% feldspar, and 10-25% lithic grains, with 5-25% clay chips
and films. Common mud rip-ups and manganese coats on clasts. Deposit typically exhibits basal
scour contacts on finer-grained sediment with up to 3 m (10 ft) of relief.
QTpaf Fine-grained axial facies of the Palomas Formation – Pebbly sand/sandstone and mudstone in thick
laminations to thick beds deposited in channel margin or floodplain settings. Unconsolidated,
non- to weakly calcareous, and massive to trough or planar cross-stratified (foresets up to 50
cm thick). Moderately well sorted, subrounded pebbles comprise no more than ~10% of a given
39
deposit and are commonly concentrated at the base of cross-beds. Sand is pale brown to light gray
(10YR 6/3 to 7/2), very fine- to coarse-grained (commonly fine to medium or medium to coarse),
moderately to very well sorted, and subangular to well rounded. Grains consist of 55-85% quartz,
10-40% feldspar (plagioclase~K-spar), and 5-15% lithics (carbonate+chert+volcanic). Deposits
often feature ellipsoidal concretions and/or rounded concretions of manganese-rich material up
to 30 cm (12 in) across. Mud rip-ups up to 45 cm (18 in) across are common at the base of
beds. Unit features up to 30% medium to thick beds of yellowish red (5YR 5/8) to olive (5Y
5/3) mudstone, typically containing fossils (including Amystoma sp. and Rana sp.; G. Morgan,
personal communication, 2015).
QTpe Eastern piedmont facies of the Palomas Formation – Sandy granule-pebble, pebble-cobble, and
pebble-cobble-boulder gravel derived from the Caballo Mountain fault block. Occurs in thin to
very thick, tabular to lenticular to wedge-shaped beds. Subordinate facies include silty sand and
silty clay in thinly laminated to very thick, tabular to lenticular beds. Cementation and sedimentary
structures vary according to relative fan position (proximal, medial, and distal). Proximal deposits
consist of massive to imbricated, poorly sorted, subangular to subrounded, sandy pebble-cobble
gravel in clast- to matrix-supported, medium to very thick, tabular beds. Proximal beds may feature
rare cross-stratification and are weakly to moderately carbonate-cemented. These facies commonly
include authigenic carbonate precipitated from shallow groundwater in gravelly gully beds (Mack
et al., 2000). Medial deposits consist of massive or imbricated to planar cross-stratified sand and
gravel in clast- to matrix-supported, medium to thick, tabular to lenticular beds. Sandy beds may
be thickly laminated. Occasional paleosols in finer-grained medial facies may feature Btk horizons
and illuviated clay (Bt) horizons above them. Distal deposits consist of poorly to moderately sorted,
subangular to rounded pebble or pebble-cobble gravel interbedded with silty to sandy facies in
mostly matrix-supported, medium to very thick, tabular to lenticular beds. Well-defined imbrication
of gravel clasts is more common in distal facies than in proximal and medial gravels. Paleosols with
Btk to K horizons are common in distal silt beds. In general, eastern piedmont facies matrix consists
of poorly to moderately sorted, subangular to subrounded, fine- to coarse-grained sand comprised
of 15-80% feldspar, 10-65% quartz, and 5-30% lithic grains. Matrix is typically reddish brown (5YR
4-5/4) to strong brown (7.5YR 4-5/4) in proximal facies, and brown (7.5YR 5/4) to light gray (10YR
7/1-2) in distal facies. Maximum thickness 110 m (361 ft).
QTper Paleo-Red Canyon alluvial fan deposits of the eastern piedmont facies of the Palomas Formation –
Siltstone, sandstone, and sandy pebble-cobble-boulder conglomerate in multi-story, thin to thick,
tabular to lenticular beds. Moderately to strongly consolidated, commonly carbonate-cemented,
mostly clast-supported, and massive to imbricated to planar cross-stratified. Scoured contacts on
underlying sandstone and siltstone beds are common. Clasts are very poorly to moderately sorted,
angular to subrounded, and consist of 45-100% pebbles, 35-45% cobbles, and 0-20% boulders
of 50-60% Paleozoic carbonates and chert, 20-30% Abo Formation siltstone and sandstone, and
10-20% granite and metamorphics. Matrix consists of yellowish red to reddish brown (5YR 4-5/6
to 5-7/4), poorly to moderately sorted, subrounded, very fine- to coarse-grained sand composed
of 40-80% lithic (carbonate+chert+mica), 40-45% feldspar, and 10-20% quartz grains. Rare stage
IV carbonate morphology with carbonate laminae and rinds on all clasts. Interfingers with QTpa
along lower 1.7 km (1.1 mi) of modern Red Canyon. 60-140 m (200-460 ft) thick.
QTpef Fine-grained eastern piedmont facies of the Palomas Formation – Clayey to silty sand with less
than 40% gravel in thin to medium, tabular to lenticular beds. Reddish yellow (5YR 6/6) to pink
(7.5YR 6-8/3-4) to very pale brown (10YR 8/2). Mostly unconsolidated and typically massive.
Less commonly, unit is horizontal-planar to ripple laminated or planar cross-stratified. Gravel
beds are clast- to matrix-supported and may be imbricated with poorly sorted, subangular to
subrounded pebbles (>60%) and cobbles (<40%). Sand consists of moderately to well sorted,
subangular to subrounded, very fine to fine grains dominated by feldspar (50-80%). Buried soils
are common and include stage I to II+ carbonate morphology with Btk, Bk, and K horizons up
to 0.8 m (2.6 ft) thick. Interfingers with basal QTpe beds to the east. Perhaps as much as 140 m
(460 ft) thick near Red Canyon, thinning northwards to approximately 30 m (100 ft).
QTpwuc Upper coarse unit of the western piedmont facies of the Palomas Formation – Uppermost unit
of western piedmont facies, consisting of sandy pebble-cobble gravel in amalgamated, laterally
continuous channel-fill complexes that are generally 2-6 m (6.6-20 ft) thick. Unit defined where
coarse channel-fills occupy more than 65% of sediment volume, the remainder being fine-grained,
40
extra-channel sediment. Basal contact is transitional with unit QTpwu and may vary in elevation by as
much as 20 m (66 ft) due to lateral terminations of lower gravelly channel-fills. These coarse channelfill complexes exhibit scoured lower contacts, with up to 1 m (3.3 ft) of relief, and typically abrupt
upper contacts (consistent with channel avulsion). Within coarse channel-fills, bedding is very thin
to thick (mostly thin to thick), commonly vague, and lenticular to tabular; 0-7% cross-stratification
includes lateral accretion sets up to 1.5 m (5 ft) thick, low-angle cross-stratification, trough crossstratification, and bar-related cross-stratification with planar foresets (up to 60 cm thick). Gravel is
generally clast-supported and imbricated, consistent with being deposited predominately by streamflow. Gravel fraction consists of 50-80% pebbles with 25-50% cobbles and 1-20% boulders. Clasts
are poorly sorted (lesser moderately sorted), subrounded (lesser rounded), and composed of crystalpoor rhyolites, 5-25% andesite-dacite (dark-colored to north, where plagioclase- and/or pyroxenephyric types dominate; lighter-colored to south, where feldspar-phyric types dominate), 10-20%
tuffs, 1-5% basaltic andesite, 0-10% Paleozoic sedimentary types (mostly <3%), 1-3% hornblendebiotite intrusive found only to the north, and trace to 1% (less commonly up to 15%, particularly
near the top of unit) vesicular basalt. Color of sandy matrix ranges from reddish brown (5YR 5/3-4)
to light reddish brown (5YR 6/4) to pink or light brown (7.5YR 6-7/4). Fine- to very coarse-grained
sand is poorly to moderately sorted, subangular to subrounded, and composed of 55-80% lithic
(volcanic), 15-30% feldspar, and 5-15% quartz grains. Sandy matrix contains notable orange clay as
chips or coatings/films (1-20%). Extra-channel sediment consists of very fine- to medium-grained
sand (mostly very fine- to fine-grained) and clayey-silty fine sand with minor (5-20%), scattered
medium to very coarse sand grains and pebbles. Color of extra-channel sediment ranges from
reddish yellow to light brown (7.5YR 6/4-6) to strong brown or reddish yellow or yellowish red
(5YR 4-5/6; 7.5YR 5-6/6). Commonly capped by a 1-1.5 m (3.3-5 ft) thick stage III-IV carbonate
horizon. Moderately to well consolidated, weakly cemented by clay. Preserved top of unit is typically
moderately to strongly cemented by soil carbonate. Maximum thickness 1.5-45 m (5-145 ft).
QTpwu Upper western piedmont facies of the Palomas Formation – Interbedded fine-grained sediment
and subordinate to subequal, laterally continuous, coarse channel-fill complexes. Upper and lower
contacts are transitional with QTpwuc and QTpwm, respectively. Base is placed at the bottom of
predominately reddish sediment, locally coinciding with a thick clayey bed. Fine-grained, extrachannel sediment consists of clayey-silty fine sand, very fine- to fine-grained sand, and clay-silt that
are in thin to thick, tabular beds that are commonly internally massive; <1-20% very thin to medium,
lenticular (lesser tabular to trough-shaped) interbeds of coarse sand ± pebbles. Locally present in
the clayey-silty fine sand and very fine- to fine-grained sand is minor (trace-25%), scattered medium
to very coarse sand ± volcanic pebbles, consistent with deposition by hyperconcentrated flows.
Clayey sediment is reddish brown to light brown to brown to light reddish brown (5-7.5YR 5-6/34; 5YR 5/4), clayey fine sand and silt is pinkish gray to pink to light brown (7.5YR 7/2 to 6-7/3-4;
5YR 6-7/2) to brown (7.5YR 5/4) to light reddish brown (5YR 6/3). Clay-silt floodplain deposits
appear most abundant along Palomas Creek. Coarse channel-fill complexes are 2-5 m (6.6-16 ft)
thick and generally laterally continuous (extending 10s to 100s of meters transverse to paleoflow
direction), with scoured bases and typically abrupt tops. These coarse channel-fills consist of clastsupported sandy gravel in vague, thin to thick (mostly thin to medium), lenticular (lesser tabular)
beds with minor (1-15%) cross-stratification up to 1 m (3.3 ft) thick and very thin to thin foresets
that are tangential, planar, or trough-cross-stratified; sandy sediment is commonly horizontal-planar
laminated to low-angle cross-stratified. Gravel is comprised of pebbles with 15-40% cobbles and
0-10% boulders. Within a bed, gravel are generally clast-supported, commonly imbricated, poorly
sorted (minor moderate sorting), and subrounded to rounded. Gravel are composed of rhyolite and
lesser felsic tuffs, together with 10-30% andesite and dacite (with plagioclase ± pyroxene phenocrysts),
0-7% basaltic andesites, 0-1% intermediate intrusive lithologies, and trace to 7% vesicular basalt
(basalt decreases near the northern quadrangle boundary). Sand that is associated with the gravels is
fine- to very coarse-grained (mostly medium- to very coarse-grained), moderately to poorly sorted,
subrounded to subangular, and composed of volcanic grains, slightly lesser feldspar grains, and
minor quartz grains. Sand color ranges from reddish brown to brown to light brown (2.5-7.5YR
4-5/4; 7.5YR 5/2-4/3; 7.5YR 5-6/3-4) to yellowish red (5YR 4/4-6) to light reddish brown (5YR
6/3) to pinkish gray (7.5YR 6/2). 0.5-15% clay argillans that coat clasts and sand grains or occur as
interstitial particles. Sand and gravel is weakly to well consolidated and non- to weakly cemented by
clay. Clayey-silty sediment is moderately to well consolidated. 10-40 m (30-120 ft) thick.
QTpwtTransitional zone below the upper western piedmont facies of the Palomas Formation –
Predominately fine-grained sediment that is redder than QTpwm and slightly less red than QTpwu.
41
Lies gradationally between these two units, both in a vertical and lateral sense (the latter mapped
south of Palomas Creek). Fine sediment consists of silt-clay (silt>clay), very fine- to mediumgrained (mostly very fine- to fine-grained) sand, and slightly silty-clayey sand in thin to thick
(mostly medium to thick), tabular beds. Locally within these fine beds are 1-10% thin to medium,
sandy pebble-cobble beds and 1-15% scattered, medium to very coarse-grained sand. Fine beds
range in color from light reddish brown to pink to light brown to pinkish gray (5YR-7.5YR 6/3-4;
7.5YR 7/3; 5YR 6/2); 0-5% reduced (yellowish-light greenish) beds. Subordinate coarse channel-fill
complexes are lenticular to laterally continuous and up to 3 m (10 ft) thick. Bedding within these
complexes is relatively thin and mostly tabular to lenticular. Gravel is comprised of pebbles with
subordinate cobbles that are poorly to moderately sorted and mostly subrounded (minor rounded).
Gravel is composed of rhyolite, lesser felsic tuffs, and 5-25% andesite-basaltic andesite. Channel-fill
sand is brown to gray (7.5YR 5/2-6/1), mostly medium- to very coarse-grained, moderately sorted,
subrounded, and composed of volcanic grains, lesser feldspar, and 10-25% quartz. Fining-upward
trends observed in individual beds or channel-fills. Interbedded carbonate ledges are observed south
of King Arroyo and are pale yellowish pink (7.5YR 9.5/2) to pinkish white (5YR 8/2), weakly to
moderately indurated, medium-bedded, and massive. These beds contain rare, randomly dispersed
pebbles up to 3.5 cm (1.4 in) across and common root mats, and likely represent spring deposits
(Mack et al., 2000). Fossils of turtles, rodents, rabbits, Equus sp., and Gomphotheriidae recovered
south of Palomas Creek. A tooth from the extinct rabbit species Sylvilagus hibbardi indicates a late
Blancan (2.5-2.0 Ma) North American Land Mammal age for this deposit (G. Morgan, personal
communication, 2014). Moderately to well consolidated; mostly non-cemented but with localized
strong cement (1-5%). Up to 35 m (115 ft) thick.
QTpwm Middle western piedmont facies of the Palomas Formation – Very fine to fine-grained sand,
silty fine sand, and silt in thin to thick (mostly medium to thick), tabular beds that are internally
massive to horizontal-planar laminated. Intertongues with QTpa. Colors are generally pink to light
brown to pinkish gray (7.5YR 7/3; 6/ 3-4; 5-7.5YR 6-7/2); clayey sediment may be light reddish
brown (5YR 6/3). Locally within the fine sediment are minor (1-10%), scattered medium to very
coarse sand grains (± trace to 5% very fine to medium pebbles) or relatively thin, coarse-grained
interbeds. <15% clayey beds. Minor (5-20%) tongues of pebbly sand and sandy pebbles are tabular
to lenticular and up to 3 m (10 ft) thick. Unit gradationally underlies QTpwt or QTpwu (in the
latter, the vertical gradation is generally <10 m thick). Coarser intervals consist of amalgamated
channel-fills with laminated to medium, lenticular to tabular, cross-stratified bedding. Occasional
fining-upward trends observed in channel-fills. Gravel consists of very fine to very coarse pebbles
and 0-20% cobbles; clasts are poorly to moderately sorted, subrounded to rounded, and composed
of rhyolite, 10-20% tuff, 5-30% intermediate volcanics, and 1% andesitic to dioritic intrusives.
Sand in gravelly beds is fine- to very coarse-grained, poorly to moderately sorted, subrounded to
subangular, and composed of volcanic and feldspar grains with 10-30% quartz; colors range from
brown (7.5YR 5/2-4) to pinkish gray-white (7.5YR 6-8/2) to pink (7.5YR 7/3). Sand in finer strata
are well sorted, subangular, and composed of quartz, 5-25% feldspar, and 15% volcanic lithic grains
and subequal mafic grains. 3-15% strongly cemented beds are mostly medium- to thick-bedded
and composed of dense calcium carbonate impregnating sand and pebbles. The basal contacts of
these beds are commonly sharp and likely represent shallow groundwater cementation features.
Cemented beds that are predominately calcium carbonate (<30% sand grains), imparting a white
color, and exhibiting laminations or vugs are inferred to be precipitated from surface water (seeps
or spring mounds; Mack et al., 2000). 1-5% localized calcium carbonate nodules and local paleoburrows. Poorly sorted and internally massive, fine sand beds (medium- to thick-bedded with 1-5%
clay-silt, 10% “floating” medium to very coarse sand grains, and 3% very fine to fine pebbles) are
common and interpreted as hyperconcentrated flows (Seager and Mack, 2003). Moderately to well
consolidated and weakly to moderately cemented by calcium carbonate. Approximately 100 m (300
ft) thick in northern quadrangle based on comparison of top of exposed unit near the town of
Williamsburg with the interpreted base of the unit in City Well 8. About 75-85 m (250-280 ft) thick
in the southern quadrangle, where interpretations of lithologic descriptions from the Barney Iorio
Fee #1 well suggest that it is underlain by 45 m (150 ft) of ancestral Rio Grande sediment.
QTpwmc Coarse sediment in the middle western piedmont facies of the Palomas Formation – Strata
dominated by coarse channel-fills, as described in unit QTpwm that are thick enough to be
mappable. 10-20 m (30-60 ft) thick.
QTpwlLower western piedmont facies of the Palomas Formation – Sediment dominated by stacked, coarse
42
channel-fills composed of clast-supported, imbricated sandy gravel. On footwall of Mud Springs
fault, lower contact locally is gradational, coarsening upward over 4-10 m (13-33 ft) as observed
immediately east of Interstate 25 along the northern quadrangle boundary. In other exposures,
the basal contact is sharp and has >1 m (3.3 ft) of scour relief. In the subsurface south of the
Mud Springs fault, the base is transitional over ~30 m (100 ft). Sediment is in thin to medium,
lenticular to tabular beds. Gravel includes pebbles, 5-40% cobbles, and 1% boulders. Clasts are
poorly sorted, subrounded (lesser rounded), and composed of pinkish to gray rhyolite, 10-25%
tuff, 10-15% plagioclase- or pyroxene-phyric andesite to basaltic andesite, 0-5% granite, trace to
1% vesicular basalt, and trace to 1% Paleozoic clasts (quartzose sandstone and limestone). About
5% of sediment is pebbly sand in thin to medium, lenticular beds. Sand is brown to reddish brown
(5-7.5YR 5/4), poorly to moderately sorted, subangular to subrounded, and fine- to very coarsegrained. Basal 1-2 m (3.3-6.6 ft) is locally strongly cemented; otherwise, generally non-cemented and
moderately consolidated. >87-91 m (285-300 ft) to north based on subsurface data in City Wells 6
and 8, appearing to thin to 17 m (56 ft) near Palomas Creek at the Barney Iorio Fee #1 well.
TERTIARY SANTA FE GROUP UNITS (PRE-PALOMAS FORMATION)
Tsupw Upper Santa Fe Group, western piedmont facies (upper Miocene) – Exposed in the bluffs north of lower
Mud Springs Canyon along the northern quadrangle boundary. Here, strata are light reddish brown (5YR
6/3-4), in medium to thick, tabular beds, and composed of: 1) siltstone and very fine- to fine-grained
sandstone (about 50-70%); and 2) fine- to medium-grained sandstone (~20%), and coarse channel-fills
(increasing up-section from 10 to 25%) Locally in the finer sand are scattered, coarse sand grains. Coarse
channel-fills are as much as 2 m (6.6 ft) thick and consist of thin to medium, tabular beds composed of
pebbly sand or sandy pebbles (with as much as 10% cobbles). Pebbles are very fine to medium, subangular
to subrounded, and composed predominately of volcanic clasts (mostly rhyolite with 10% tuffs, 10%
intermediate volcanics, 1% basaltic andesite, and perhaps trace basalt) together with 1-5% chert and 0-1%
granite (both from the Mud Springs Mountains). Sub- or superjacent to large channel-fills may lie floodplain
deposits of mudstone, siltstone, and very fine to fine-grained sandstone (commonly horizontal-planar to
ripple-laminated). Proportion of cemented beds increases up-section from 5 to 50%. Cementation is often
nodular (5-10 cm across) and probably controlled by bioturbation or burrowing. At top of exposure lies a
1-2 m (3.3-6.6 ft) thick, laterally extensive, calcium carbonate bed mixed with 20-40% sand and gravel. Well
consolidated. Unit is >20 m (60 ft) thick in exposures in northernmost of quadrangle; perhaps up to 400 m
(1300 ft) thick in the Barney Iorio Fee #1 well.
Tsubf Upper Santa Fe Group, basin-floor facies (upper Miocene) – Thin to thick, tabular beds of light reddish
brown to yellowish red (5YR 6/4-5/6), very fine- to medium-grained sand and clayey-silty sand. Sand is
moderately sorted and subangular to subrounded. Minor (~5%) beds composed of very fine- to very
coarse-grained sand with 5% pebbles. Pebbles are mostly very fine to fine, poorly to moderately sorted,
angular to rounded (mostly subangular), and composed largely of aphanitic (likely felsic) volcanic rocks,
~25% chert, trace to 10% greenish sandstone (Mesozoic?), ~5% granite, and ~5% gneissic (Proterozoic)
clasts. Moderately to well consolidated, with 5% well-cemented, medium to thick layers. 165-180 m (550600 ft) thick based on interpretations of the Barney Iorio Fee #1 well log.
Tsus Upper Santa Fe Group, silicified (upper Miocene) – Strongly silicified Santa Fe Group conglomerate found
in a sliver of the Hot Springs fault zone in the eastern part of the quadrangle. Clasts consist of poorly
sorted, angular to subangular pebbles and cobbles of aphanitic volcanic lithologies, chert, granite, and
metamorphic rocks. Matrix is replaced by silica cement that is weak red (10R 4-5/) to reddish brown (2.5YR
4-5/). Total thickness >15 m (50 ft).
43
PALEOZOIC BEDROCK UNITS
Om
Montoya Formation (middle to upper Ordovician)
Oma Aleman Member – Dark gray to dark brownish gray, thin- to medium-bedded, massive to occasionally
laminated, non- to sparsely fossiliferous dolostone and subordinate wackestone and packstone. Less
commonly features light to medium gray or purplish brown, medium-bedded, massive to laminated
packstone interbedded with jasperoid. Packstone contains lacy networks of dark brown chert. Jasperoid
contain relict nodules of limestone and secondary hydrothermal alteration products of quartz and barite.
Contains the brachiopods Rafinesquina and Zygospira in the lower half (Mason, 1976). Forms dark colored
slopes with isolated outcrops. 53 m (174 ft) thick in quadrangle.
Oml Lower Member of the Montoya Formation – Brownish gray, cherty dolostone overlying white to medium
gray, quartzose sandstone with a dolomitic matrix. Dolostone occurs in thick to very thick, tabular beds
and is massive to laminated with laminae of dark brown chert. Vertical burrows in-filled by light gray
chert. Poorly outcropping jasperoid observed in upper 12 m (40 ft). Sandstone occurs in medium, tabular
to lenticular, reverse-graded beds and is fine- to medium-grained. In upper part, sandstone grades to
subangular or subrounded granules to pebbles of quartz and black chert interfingering with dolostone.
Total thickness 37 m (121 ft).
Oep El Paso Formation (lower Ordovician)
Oepb Bat Cave Member – Medium to dark gray or pinkish gray, ledge-forming, thin- to thick-bedded, massive to
wavy-bedded to occasionally ripple laminated, fossiliferous, cherty wackestone to grainstone. At least two
beds of light to brownish gray, matrix-supported, medium-bedded, massive limestone breccia occur in the
upper half. Clasts in these beds feature poorly sorted, angular fragments of limestone and dolostone in a
fine- to medium-grained grainstone matrix. Fossils include brachiopods, crinoid columnals, trilobites, and
stromatolites. The latter occur as 3 cm (1.2 in) thick algal mats or domal structures up to 30 cm (12 in) in
diameter. Chert occurs as wavy laminae, vertical veinlets up to 6 cm (2.4 in) wide, or pebble-sized nodules
to extensive lenses forming protruding layers up to 40 cm (16 in) thick. Total thickness approximately 65 m
(213 ft).
Oeps Sierrite Limestone – Medium to dark brownish gray or occasionally reddish, thin- to medium-bedded,
tabular, mostly massive, sparsely fossiliferous, cherty, dolomitic packstone. Occasional dark gray dolostone
beds up to 15 cm (6 in) thick. Chert occurs in 1-3 cm (<1.2 in) wavy bands, vertical veinlets up to 2 cm (0.8
in) wide, ribbons up to 15 cm (6 in) wide, or lenses and nodules up to 6 cm (2.4 in) thick, and weathers black
or dark brown. Weakly to strongly bioturbated, with vertical burrows filled with dolomite. Gradational
basal contact with Bliss Formation features several very thin (1-2 cm) layers of gray to very dark brown,
interbedded siltstone and limestone. Elsewhere, lower 3-3.5 m (10-12 ft) consists of limestone altered to
jasperoid. Total thickness 53 m (174 ft).
_Ob Bliss Formation (upper Cambrian to lower Ordovician) – Very dark brown to nearly black, well indurated,
thin- to medium-bedded, occasionally wavy-bedded, tabular, massive to broadly cross-stratified sandstone.
Well sorted, subangular to subrounded, quartzose, and very fine- to fine-grained with subordinate, noncalcareous siltstone. Common peloidal glauconite. Generally forms slopes beneath ledges of Oeps. Total
thickness 12 m (39 ft).
PROTEROZOIC BEDROCK UNITS
=u Plutonic and metamorphic rocks, undivided (Paleo- to Mesoproterozoic) – Granitic gneiss, quartzofeldspathic schist, amphibolite, metasiltstone, and granite in unknown proportions. See individual
descriptions for Proterozoic granite and metamorphic rocks. Total thickness unknown.
=g Granite (Paleo- to Mesoproterozoic) – Pink to pinkish gray to red, hypidiomorphic granular,
44
phaneritic, fine- to very coarse-grained, locally gneissic granite exposed in footwall of Hot Springs
fault. Phenocrysts include plagioclase, microcline, quartz, and biotite. Exsolution lamellae of
plagioclase are commonly found in microcline crystals and define a perthitic texture. Groundmass
is composed of feldspar, quartz, and minor chlorite. Quartz veins are common and range from mm
to m-scale thickness. Pink granite is poorly to moderately foliated; gneissic granite is well foliated.
Total thickness of plutonic rocks unknown.
=m Metamorphic rocks (Paleo- to Mesoproterozoic) – Unit mapped where metamorphic rocks constitute
over 60% of exposure. Dark gray gneiss is commonly intruded by granitic to quartzose pegmatite
veins up to 25 cm (10 in) wide. Quartzo-feldspathic schist is dark to tannish gray and micaceous
(biotite+muscovite). Both gneiss and schist are strongly foliated. Metamorphic units often exhibit
low amplitude (less than 30 cm) folding and may be boudinaged. Occasional amphibolite pods
(roof pendants) contain phenocrysts of plagioclase, biotite, and hornblende, and are <10 m (33 ft) in
diameter. Minor reddish brown metasiltstone is observed in places. Total thickness unknown.
SUBSURFACE UNITS
QTpwltTransitional base of the lower western piedmont facies of the Palomas Formation (lower Pliocene) – Pinkish
gray to light brown to pink (7.5YR 7/2-3; 6/3) clay, silt, and fine sand interbedded with minor channelfills of coarse sand and felsic-intermediate volcanic pebbles (with trace dark, aphanitic clasts that could be
basalt). Interpreted to be 51 m (169 ft) thick in the Barney Iorio Fee #1 well. Unit is only ~6 m (20 ft) thick
where QTpwl/Tsupw contact is exposed and is accordingly subsumed into QTpwl. Cross-section only.
Tsu
Upper Santa Fe Group underlying the Palomas Formation (middle to upper Miocene) – Units Tsupw and
Tsubf, undivided. As described in the Barney Iorio Fee #1 well log, the unit consists of interbedded clay
and sandstone. Clays are sticky and mostly pink at 632-802 ft, gray at 802-975 ft, and pink to red at 975-1165
ft. At 1170-2100 ft, the unit is harder (better cemented), exhibits gypsum laminations, and may contain ash
and/or carbonate beds. ~600 m (1970 ft) thick. Cross-section only.
Tsl
Lower Santa Fe Group (Oligocene to middle Miocene) – Relatively well-cemented Santa Fe Group consisting
of volcaniclastic sandstone and conglomerates. Correlative to the Hayner Ranch Formation and possibly to
the Thurman Formation (Seager et al., 1971; Seager et al., 1982). Described using exposures on the Skute
Stone Arroyo quadrangle (Koning et al., 2015). Estimated to be 1100 m (360 ft) thick using cross-section
on Skute Stone Arroyo quadrangle. Cross-section only.
45
APPENDIX B
Clast-count data from the Williamsburg 7.5’ quadrangle
This appendix contains tabulated clast-count data (lithology type and mean diameter, except where noted) from a
variety of geologic units exposed in the Williamsburg quadrangle. These units include Pleistocene terrace and alluvial
fan deposits, Palomas Formation units, and one count from piedmont facies of the upper Santa Fe Group pre-dating
the Palomas Formation. Location coordinates for all counts are given in UTM NAD83 zone 13S, except where noted.
Lithology abbreviations include the following: Tb = basalt (typically Pliocene basalt flows, although a single basalt
clast in Table A.15 likely represents an older, now-eroded flow), Tba = basaltic andesite, Tvp = Vicks Peak tuff, Thm
= Hells Mesa tuff, Tkn = Kneeling Nun tuff, Trrl = Luna Park trachyandesite of the Red Rock Ranch Formation,
Tad = intrusive andesite-diorite, Pa = Abo Formation, _Ob = Bliss Formation, and Pz = Paleozoic.
47
4
3
2
4
2
5.5
5
20
n
% total
16
4
8
2
4.0
4
4
intermediate
intrusive
8
2
2.3
2
2.5
8
2
3.3
4.5
2
Tb Tba
8
2
2.5
2
3
flow-banded
rhyolite
8
2
4.3
5
3.5
Pa
6
8
2.5
10
8.1
4
16
mean diameter
(cm)
n
% total
12
3
6.3
5
15.5
4.5
lithic tuff
8
2
3.0
2
4
aphanitic
rhyolite
8
2
6.5
6
7
Pa
8
2
2.3
2.5
2
aphanitic andesite
3659174N, 286970E
UTM Location
dacite
August 20, 2014
Date
8
2
6.8
4.5
9
Tba
4
1
2.0
2
4
1
6.0
6
4
1
3.5
3.5
Tb
dacite
amphibolite
TABLE B.2 CLAST TYPE AND DIAMETER (cm) FOR UNIT Qtr4
3.3
mean diameter
(cm)
3.8
6
2.5
2.5
aphanitic
rhyolite
3661879N, 284672E
UTM Location
Tkn
July 1, 2014
Date
TABLE B.1 CLAST TYPE AND DIAMETER (cm) FOR UNIT Qtp3
4
1
10.0
10
COb
4
1
3.0
3
4
1
2.5
2.5
lithic tuff
4
1
12.0
12
flow-banded
rhyolite
Pz limestone
4
1
5.0
5
green siltstone
4
1
4
1
18.0
18
jasperoid
2.0
2
plagioclase-phyric
andesite
4
1
9.5
9.5
Pz limestone
4
1
3.0
3
volcaniclastic
sandstone
4
1
2.5
2.5
granite
4
1
15.0
15
Tkn
4
1
4.0
4
aphanitic tuff
n = 25
4
1
7.5
7.5
intermediate
intrusive
n = 25
48
3
8
2
4
3
4
13
n
% total
10
3
2.8
3
2.5
3
10
3
6.3
8
3
8
Thm/Tkn
2
2.5
4
3
4.5
4
3
3.1
8
2.5
1
2.5
5.5
1
3
5.5
2.9
8
16
n
% total
16
2
2.5
14
7
2.9
4
1
3.5
1
2.5
2.5
5.5
dark packstone
or grainstone
7
2
4.0
3
5
7
2
3.3
3
3.5
Pa granite
10
5
2.1
3
1
2
2.5
2
gray wackestone
3664278N, 288842E
UTM Location
medium gray
limestone with
fusulinids
February 12, 2014
Date
brown packstone
mean diameter
(cm)
10
3
2.3
2.5
2
2.5
Tb
7
2
5.3
5.5
5
8
4
1.5
2
2
1
1
3
1
3.0
3
3
1
7.5
7.5
dacite
3
1
8.0
8
lithic tuff
3
1
6.5
6.5
trachyte
3
1
7.5
7.5
plagioclasequartz-phyric
tuff
3
1
7.5
7.5
Tvp
n = 30
n = 50
8
4
2.3
2
2
3
2
6
3
3.8
4.5
4
3
6
3
1.5
1.5
1.5
1.5
4
2
2.5
4
1
4
2
2.3
2
2.5
2
1
4.5
4.5
2
1
1.5
1.5
2
1
3.0
3
2
1
4.0
4
medium gray reddish wacke- tan silt- altered lime- pink nodular calcareous
dark gray
chert COb
grainstone
stone
stone
stone
siltstone
siltstone
dolostone
7
2
5.0
5
5
plagioclase-phyric
Tba COb
andesite
black fossiliferous carbonate
TABLE B.4 CLAST TYPE AND DIAMETER (cm) FOR UNIT Qfo
10
5.3
mean diameter
(cm)
3.9
7
5
2.5
quartz-phyric
quartzite
tuff
3655626N, 285250E
UTM Location
aphanitic
rhyolite
October 6, 2014
Date
TABLE B.3 CLAST TYPE AND DIAMETER (cm) FOR UNIT Qtr5
49
1
1
1
1
1
1
11
9
4
6
3
6
3
NA
1
1
1
4
2
NA
1
1
4
2
NA
1
1
2
1
NA
1
chert /
jasperoid
Lithology abbreviations: aph. = aphanitic, rhy. = rhyolite, and. = andesite, dac. = dacite.
11
5
NA
1
1
1
basalt
Clast dimensions not measured.
28
% total
5
NA
1
1
1
1
flow-banded
aph.
lithic tuff
rhyolite
and.b
b
13
n
NA
1
1
1
1
1
aph.
rhy.b
a
NA
mean diameter
(cm)a
1
1
1
1
1
1
1
1
NA
1
1
1
1
1
plagioclase-phyric
Tkn
andesite
3666426N, 285122E
UTM Location
Tba
July 20, 2015
Date
TABLE B.5 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwuc
2
1
NA
1
2
1
NA
1
2
1
NA
1
2
1
NA
1
plagioclase-bio- plagioclase-pydac.b Pa tite-quartz-phyric roxene-phyric
tuff
andesite
2
1
NA
1
2
1
NA
1
2
1
NA
1
2
1
NA
1
quartz-sanvolcaniclastic
idine-phyric Tad Tvp
sandstone
tuff
n = 47
TABLE B.6 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwuc
Date
May 1, 2015
UTM Location
3663131N, 284396E
n = 30
hornplagioclase-phyric
Tb blende-phyric
Pz carbonate jasperoid
andesite
andesite
Tkn
flow-banded
rhyolite
Tba
5
3
6.5
9
10
5
2
3
7
7.5
3
2
4
12.5
11
10
6.5
8.5
11
4.5
9
5
3.5
7.5
5
2
5
5
12
13
mean diameter
(cm)
6.4
6.4
7.8
7.8
6.5
3.5
7.5
5.0
n
10
5
5
4
2
2
1
1
% total
33
17
17
13
7
7
3
3
50
51
2
1
5
2.5
4
5
20
n
% total
12
3
4.3
4
4.5
4.5
basalt
3664141N, 284198E
September 26, 2013
UTM coordinates in NAD27, zone 13S.
16
2.3
a
3.5
5
4.7
mean diameter
(cm)
2.5
4
7
Tba
a
plagioclase-phyric
andesite
UTM Location
Date
12
3
2.3
2
2.5
2.5
chert
12
3
2.0
1.5
3
1.5
gray siltstone
TABLE B.7 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwuc
8
2
4.0
3.5
4.5
8
2
2.8
2
3.5
quartz-biotite-plavolcaniclastic
gioclase-phyric
sandstone
tuff
4
1
4.0
4
Tkn
4
1
3.5
3.5
dacite
4
1
3.0
3
Pa
n = 25
52
1
1
1
1
1
1
1
1
1
1
1
1
1
1
13
25
n
% total
18
9
14
7
NA
1
1
1
1
1
1
1
10
5
NA
1
1
1
1
1
flow-banded
Tkn
rhyolite
Clast dimensions not measured.
NA
1
1
1
1
mean diameter
(cm)a
a
1
1
NA
1
1
1
aphanitic
rhyolite
3666354N, 285128E
UTM Location
Tba
July 20, 2015
Date
8
4
NA
1
1
1
1
plagioclase-phyric
andesite
4
2
NA
1
1
Tvp
2
1
NA
1
chert/jasperoid
TABLE B.8 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwu
2
1
NA
1
dacite
2
1
NA
1
lithic tuff
2
1
NA
1
Pa
2
1
NA
1
2
1
NA
1
2
1
NA
1
2
1
NA
1
saniplagioclase-pyrox- aphanitic
dine-phyric Tad
ene-phyric andesite andesite
tuff
2
1
NA
1
Tb
2
1
NA
1
volcaniclastic
sandstone
n = 51
TABLE B.9 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwu
Date
May 1, 2015
UTM Location
3667511N, 286410E
n = 30
Tkn
Tba
flow-banded
rhyolite
Tb
dacite
Pa
plagioclase-phyric
andesite
lithic tuff
2
3.5
3
3.5
4.5
8.5
10
4
3
4
3
3
3
1.5
4.5
4.5
3.5
3.5
2.5
2
4.5
3
6
4.5
6
6
3.5
2
9
4
mean diameter
(cm)
4.3
3.9
3.7
3.0
3.8
5.0
7.3
4.0
n
8
6
5
3
2
2
2
1
% total
27
20
17
10
7
7
7
3
53
54
23
a
8
10
n
% total
12
5
NA
1
1
1
1
1
aphanitic
rhyolite
Clast dimensions not measured.
19
NA
NA
mean diameter
(cm)a
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Tkn
12
5
NA
1
1
1
1
1
plagioclase-phyric
andesite
3666279N, 285225E
UTM Location
Tba
July 20, 2015
Date
9
4
NA
1
1
1
1
chert/jasperoid
7
3
NA
1
1
1
flow-banded
rhyolite
TABLE B.10 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwt
7
3
NA
1
1
1
Tvp
2
1
NA
1
lithic tuff
2
1
NA
1
aphanitic
andesite
2
1
NA
1
2
1
NA
1
sanidine-phyric
Tad
tuff
2
1
NA
1
Tb
n = 43
TABLE B.11 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwm
Date
May 1, 2015
UTM Location
3662874N, 284569E
n = 30
Tkn
flow-banded
rhyolite
Tba
plagioclase-phyric
andesite
Tb
Pa
chert
dacite
4
3
4.5
4
3.5
2
1.5
6
3
4
7.5
4.5
1.5
2
3
1
4
2.5
5
2.5
2
2.5
3
2
3
3.5
3
3
4
5
mean diameter
(cm)
3.2
2.7
4.3
3.5
3.3
2.0
1.5
6.0
n
7
6
6
4
3
2
1
1
% total
23
20
20
13
10
7
3
3
55
56
7
3.5
1.5
0.5
1
3.5
5
0.5
1
4
3.5
1
2
8.5
8
18
36
n
% total
16
3.1
9
4
1.5
3
4.5
1.5
1.5
4
1.5
3.1
mean diameter
(cm)
2.5
2.5
3
Tba
12
6
2.1
2
2
0.5
1.5
2
4.5
flow-banded
rhyolite
12
6
2.8
4
2.5
1
5
3
1.5
plagioclase-pyroxene-phyric
andesite
3658315N,
283940E
UTM Location
Tkn
September 3, 2014
Date
6
3
4.2
8
2.5
2
dacite
6
3
2.3
4
2
1
volcaniclastic
sandstone
TABLE B.12 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpwm
4
2
1.5
2
1
aphanitic rhyolite
4
2
4.5
4
5
Tb
2
1
2.5
2.5
chert
2
1
8.5
8.5
plagioclase-phyric
andesite
n = 50
57
9
11
22
n
% total
18
3.8
1
3.0
mean diameter
(cm)
8.5
2
2.5
2
1
4
1.5
5
2
7.5
1
1
9.5
3
4
4
2.5
2.5
2.5
phospatic limestone
16
8
2.4
1
4
2.5
1
3.5
2
2.5
2.5
10
5
4.5
4
4
6.5
5
3
10
5
4.1
4.5
1.5
1.5
11
2
6
3
2.2
2
3.5
1
non-fossiliferous
gray fossiliferdark dolostone
green packstone
limestone
ous limestone
3660038N, 289206E
UTM Location
Pa
January 31, 2014
Date
TABLE B.13 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTper
6
3
2.8
3.5
3
2
chert
4
2
4.0
1
7
dark fossiliferous
limestone
4
2
2.0
2
2
quartzose
sandstone
4
2
4.3
4
4.5
granite
n = 50
58
7.9
5
3.1
5
14
n
% total
14
4
3.5
mean diameter
(cm)
12
3.5
7
3
10
6.5
4.5
1
Tkn
11
4
4.6
6.5
2
2
8
red-tan, very fine
to fine sandstone
3655493N, 283871E
UTM Location
quartzite
May 1, 2015
Date
9
3
5.3
5.5
3
7.5
flow-banded
rhyolite
9
3
5.0
4.5
5
5.5
Trrl
9
3
6.5
3
7.5
9
chert/jasperoid
TABLE B.14 CLAST TYPE AND DIAMETER (cm) FOR UNIT QTpa
6
2
2.5
3.5
1.5
6
2
7.3
6.5
8
granite Tba
3
1
11.0
11
laminated limestone
3
1
7.0
7
plagioclase-phyric
andesite
3
1
0.5
0.5
petrified
wood
n = 30
TABLE B.15 CLAST TYPE AND DIAMETER (cm) FOR UNIT Tsupw
Date
May 1, 2015
UTM Location
3667511N, 286410E
n = 35
Tba
flow-banded
rhyolite
granite
plagioclase-phyric
chert/jasperoid
andesite
1
2.5
2
2
1
3
2
1
4
1
1.5
6
3
3
1.5
3.5
2.5
1
3
1
2.5
4
0.5
0.5
Pa
Tkn
Pz limestone
Tb
dacite
3
2.5
2
1
4
2.5
1.5
2
0.5
1
2.5
mean diameter (cm)
2.6
1.9
1.6
3.0
2.3
2.3
1.3
1.0
4.0
2.5
n
9
7
7
3
2
2
2
1
1
1
% total
26
20
20
9
6
6
6
3
3
3
59
APPENDIX C
Paleocurrent data from the Williamsburg 7.5’ quadrangle
This appendix contains tabulated paleocurrent direction data (azimuthal) measured from imbrication of gravels from
a variety of geologic units exposed in the Williamsburg quadrangle. These units include Pleistocene terrace and
alluvial fan deposits as well as Palomas Formation units. Location coordinates for all measurements are given in
UTM NAD83 zone 13S. Mean paleocurrent directions from imbrication are shown on the geologic map.
TABLE C.1 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-58
Flow direction measurements
Northing
3662317
130
Easting
279340
140
Unit
QTpwu
125
Mean
145
125
Median
145
147
n
9
168
145
145
181
TABLE C.2 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-66
Flow direction measurements
Northing
3662681
161
184
196
128
127
Easting
280698
152
152
150
142
127
Unit
QTpwu
187
159
212
187
Mean
177
200
220
142
185
Median
182
198
228
147
146
n
42
216
228
147
132
216
228
125
156
191
204
179
156
191
204
168
152
191
198
143
277
TABLE C.3 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-70
Flow direction measurements
Northing
3662587
175
212
207
Easting
281026
165
215
197
Unit
QTpwu
120
195
215
Mean
195
232
193
187
Median
197
224
193
220
n
26
209
237
220
196
154
209
172
180
172
165
217
61
TABLE C.4 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-71a
Flow direction measurements
Northing
3662517
98
151
107
128
Easting
281262
128
192
100
135
Unit
QTpwu
116
166
200
148
Mean
132
162
157
130
152
Median
132
100
145
122
152
n
38
107
141
126
155
110
97
121
147
115
77
113
156
152
113
134
146
85
134
TABLE C.5 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-71b
Flow direction measurements
Northing
3662520
273
282
293
320
Easting
281268
273
308
293
291
Unit
QTpwu
273
308
284
291
Mean
282
273
243
271
323
Median
279
273
250
271
238
n
35
273
250
271
273
279
289
260
279
324
260
278
317
282
293
317
TABLE C.6 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-79
Flow direction measurements
Northing
3666658
160
172
163
144
120
Easting
283466
160
167
131
161
133
149
Unit
QTpwuc
153
167
140
161
Mean
159
153
175
140
163
114
Median
161
158
175
135
163
162
n
59
156
160
172
163
154
145
160
156
163
196
148
165
156
132
170
148
154
152
165
185
155
150
152
162
154
173
178
164
162
170
173
168
164
162
170
180
198
162
122
136
150
168
177
179
62
TABLE C.7 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-85
Flow direction measurements
Northing
3667172
136
68
97
123
168
Easting
282824
136
62
78
82
87
Unit
QTpwuc
127
70
124
95
87
Mean
105
125
86
133
116
83
Median
103
74
91
91
110
83
n
70
85
108
103
110
83
103
130
103
94
91
121
88
103
118
103
101
88
93
89
100
101
115
80
107
100
101
113
105
107
100
103
136
106
136
85
138
136
128
113
113
126
100
123
113
87
TABLE C.8 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-88
Flow direction measurements
Northing
3666719
150
110
140
60
76
Easting
282956
150
98
130
108
100
Unit
QTpwu
150
120
130
108
100
Mean
113
92
111
130
108
85
Median
111
92
111
130
108
n
44
145
111
95
95
145
111
70
88
148
111
88
100
148
116
95
91
148
116
111
160
TABLE C.9 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT W-94
Flow direction measurements
Northing
3666301
194
184
259
236
223
Easting
283650
208
232
238
252
247
Unit
QTpwu
196
211
258
222
265
Mean
234
204
171
258
224
265
Median
239
204
220
265
225
215
n
50
204
239
265
216
268
210
276
265
243
277
201
276
239
244
272
199
258
239
244
272
166
259
244
221
250
63
TABLE C.10 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-115
Flow direction measurements
Northing
3662706
220
82
212
272
308
Easting
281709
220
105
226
275
332
Unit
QTpwm
221
197
226
252
Mean
241
221
237
317
310
Median
239
226
238
225
304
n
42
217
257
272
360
239
220
239
360
239
126
321
248
137
254
241
280
115
197
272
286
TABLE C.11 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-116b
Flow direction measurements
Northing
3662651
198
107
100
189
Easting
281652
209
156
51
147
Unit
QTpwm
55
149
110
183
Mean
127
73
135
108
140
Median
118
93
112
108
147
n
35
127
104
128
106
115
152
117
248
117
66
118
115
124
118
131
TABLE C.12 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-119
Flow direction measurements
Northing
3662216
172
195
176
133
160
Easting
281780
172
173
162
133
160
Unit
QTpwu
130
182
166
133
177
Mean
151
157
182
166
111
177
Median
155
147
202
155
111
122
n
57
145
165
155
110
162
152
165
155
90
113
143
136
152
90
129
175
169
158
90
132
165
155
201
85
153
172
118
176
153
176
118
174
64
TABLE C.13 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-120_1
Flow direction measurements
Northing
3662480
176
Easting
281596
165
Unit
QTpwu
165
Mean
157
166
Median
165
195
n
9
162
132
150
101
TABLE C.14 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-120_2
Flow direction measurements
Northing
3662480
60
56
36
Easting
281596
88
15
47
Unit
QTpwu
40
67
Mean
48
40
67
Median
40
60
67
n
22
60
35
92
40
20
40
28
35
34
35
TABLE C.15 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-120_3
Flow direction measurements
Northing
3662479
124
74
117
Easting
281600
124
84
128
Unit
QTpwu
124
96
127
Mean
122
124
122
121
Median
124
124
122
130
n
27
140
122
178
140
122
155
140
122
101
119
74
140
65
TABLE C.16 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-120_4
Flow direction measurements
Northing
3662480
202
188
150
166
146
Easting
281599
229
202
150
166
146
Unit
QTpwu
204
225
181
166
146
Mean
186
162
208
207
167
147
Median
186
180
208
209
176
192
n
62
202
215
207
216
192
186
215
205
227
182
186
159
205
227
179
186
159
106
218
184
225
209
215
163
200
225
177
208
163
202
177
172
135
185
150
196
135
TABLE C.17 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-120b
Flow direction measurements
Northing
3662474
199
170
160
Easting
281598
150
170
160
Unit
QTpwu
166
163
177
Mean
174
187
163
177
Median
170
187
166
179
n
31
192
166
180
198
159
180
198
159
168
170
192
168
170
192
175
164
TABLE C.18 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-127b
Flow direction measurements
Northing
3661898
287
171
135
122
100
Easting
282453
269
98
135
122
140
Unit
QTpwu
269
98
135
163
108
Mean
178
292
98
158
93
289
Median
145
268
93
135
93
289
n
71
268
95
140
93
289
250
95
140
99
296
246
167
151
110
296
246
167
151
110
341
244
99
145
110
307
295
162
150
129
324
295
162
153
129
295
114
137
171
282
111
137
103
348
123
113
104
66
TABLE C.19 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-130_1
Flow direction measurements
Northing
3661576
167
76
151
126
Easting
282802
197
95
168
126
Unit
QTpwu
187
100
168
103
Mean
146
147
100
185
103
Median
153
126
181
155
117
n
36
127
181
155
83
124
225
156
124
180
159
166
127
168
166
151
168
TABLE C.20 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-130_2
Flow direction measurements
Northing
3661576
42
124
106
Easting
282802
70
129
101
Unit
QTpwu
70
129
101
Mean
96
117
96
101
Median
102
103
40
124
n
28
103
40
112
92
40
112
92
114
94
92
114
124
106
TABLE C.21 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-143b
Flow direction measurements
Northing
3665547
85
122
114
126
99
Easting
284807
108
116
92
95
99
Unit
QTpwu
108
106
104
114
87
Mean
108
104
111
104
108
87
Median
108
104
103
143
114
97
n
53
104
98
143
114
105
96
98
143
114
105
118
98
108
119
116
110
109
113
92
116
112
109
106
92
112
99
126
92
67
TABLE C.22 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-143b-upper
Flow direction measurements
Northing
3665547
157
133
225
Easting
284807
143
90
137
Unit
QTpwu
135
127
125
Mean
138
113
138
99
Median
134
92
169
108
n
28
167
218
65
132
122
98
169
122
112
165
150
138
207
TABLE C.23 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-144b
Flow direction measurements
Northing
3665537
182
125
Easting
284967
168
183
Unit
QTpwm
176
173
Mean
181
210
224
Median
183
188
157
n
19
183
195
185
199
167
203
182
190
150
TABLE C.24 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-145
Flow direction measurements
Northing
3665463
166
164
172
112
116
Easting
284954
166
105
187
132
116
Unit
QTpwm
172
150
177
103
112
Mean
130
172
156
142
228
68
Median
132
163
154
160
97
156
n
57
215
151
185
15
107
143
151
148
54
110
143
214
93
98
110
143
108
93
198
75
86
95
132
91
100
94
49
49
160
160
131
77
68
TABLE C.25 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-148_1
Flow direction measurements
Northing
3665693
88
124
77
Easting
284941
88
183
108
Unit
QTpwuc
88
54
120
Mean
106
73
64
125
Median
108
125
68
156
n
25
125
82
103
127
114
133
118
89
128
89
TABLE C.26 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-148_2
Flow direction measurements
Northing
3665693
256
Easting
284941
270
Unit
QTpwuc
277
Mean
274
224
Median
270
327
n
11
311
250
294
289
265
250
TABLE C.27 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-148_3
Flow direction measurements
Northing
3665693
116
93
Easting
284941
116
110
Unit
QTpwuc
97
110
Mean
106
97
116
Median
110
97
116
n
15
103
103
110
110
93
69
TABLE C.28 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-149
Flow direction measurements
Northing
3665704
92
115
140
168
109
Easting
284910
112
86
137
168
116
Unit
QTpwuc
101
87
137
168
143
Mean
103
98
85
137
168
104
Median
107
123
77
137
162
104
n
128
123
134
130
163
98
180
128
130
158
103
180
45
90
188
106
186
45
111
140
46
180
58
127
43
46
180
62
118
55
46
180
109
118
55
108
32
109
99
60
108
32
108
99
58
23
171
123
68
118
0
57
123
68
117
108
59
148
68
136
99
59
148
44
105
99
85
94
44
120
107
73
94
44
113
138
73
112
0
147
144
68
107
23
146
86
81
107
31
138
90
83
61
112
128
90
96
122
37
91
115
122
22
171
TABLE C.29 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-152_1
Flow direction measurements
Northing
3665783
87
98
89
97
Easting
284662
134
105
89
97
Unit
QTpwuc
134
94
98
122
Mean
97
165
94
162
126
Median
94
100
92
162
n
34
100
78
166
85
78
91
62
99
91
29
26
62
46
67
65
70
TABLE C.30 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-152_2
Flow direction measurements
Northing
3665783
295
276
225
190
275
Easting
284662
318
276
221
169
186
Unit
QTpwuc
318
308
221
307
237
Mean
251
318
253
232
307
243
Median
250
265
253
233
315
243
n
47
287
244
196
259
189
255
236
183
250
189
255
228
183
250
292
228
256
275
292
225
243
275
TABLE C.31 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159b_1
Flow direction measurements
Northing
3664586
170
Easting
284835
128
Unit
QTpwt
128
Mean
124
126
Median
125
124
n
8
124
97
97
TABLE C.32 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159b_2
Flow direction measurements
Northing
3664589
164
128
195
177
198
Easting
284831
145
122
195
177
252
Unit
QTpwt
145
168
163
199
252
Mean
183
183
144
177
199
269
Median
177
169
144
192
103
179
n
71
165
148
192
103
242
165
148
125
184
250
140
148
202
202
246
152
190
198
264
264
123
138
215
264
264
124
194
215
268
258
122
155
190
268
133
185
170
259
110
152
234
140
101
152
234
140
71
TABLE C.33 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159b_3
Flow direction measurements
Northing
3664591
119
122
Easting
284826
110
122
Unit
QTpwt
122
Mean
104
119
Median
119
82
n
12
38
91
121
129
71
TABLE C.34 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159b_4
Flow direction measurements
Northing
3664595
170
Easting
284823
110
Unit
QTpwt
130
Mean
104
180
Median
119
176
n
12
184
164
173
173
167
164
TABLE C.35 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159c_1
Flow direction measurements
Northing
3664592
119
Easting
284789
119
Unit
QTpwu
110
Mean
122
133
Median
126
133
n
10
85
133
133
154
103
72
TABLE C.36 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159c_2
Flow direction measurements
Northing
3664592
17
344
Easting
284786
17
10
Unit
QTpwu
34
10
Mean
9
22
Median
10
18
n
13
18
0
0
353
353
TABLE C.37 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-159c_3
Flow direction measurements
Northing
3664596
185
Easting
284778
185
Unit
QTpwu
200
Mean
194
204
Median
193
n
4
TABLE C.38 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-160_1
Flow direction measurements
Northing
3664751
97
50
112
96
122
Easting
284508
97
89
112
117
122
Unit
QTpwu
99
72
104
82
147
Mean
99
99
60
141
85
118
Median
97
76
138
150
170
118
n
62
91
67
101
175
138
93
64
110
143
138
63
64
139
47
129
88
88
51
27
104
88
53
72
70
75
85
134
72
136
85
59
103
103
95
52
138
122
73
TABLE C.39 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-160_2
Flow direction measurements
Northing
3664752
68
75
Easting
284501
78
116
Unit
QTpwu
110
116
Mean
91
110
74
Median
99
109
74
n
17
109
63
56
105
85
103
99
TABLE C.40 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-160_3
Flow direction measurements
Northing
3664758
84
131
Easting
284494
68
64
Unit
QTpwu
68
107
Mean
141
182
68
Median
131
116
68
n
21
131
216
137
216
137
196
135
237
131
235
235
TABLE C.41 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-160_4
Flow direction measurements
Northing
3664753
134
Easting
284502
166
Unit
QTpwu
153
Mean
178
165
Median
171
220
n
10
175
201
195
217
153
74
TABLE C.42 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-168_1
Flow direction measurements
Northing
3664105
118
140
118
135
120
Easting
284629
171
87
118
135
120
Unit
QTpwu
171
80
117
135
103
Mean
130
145
158
117
135
114
Median
130
145
154
117
135
n
44
157
136
124
135
162
133
122
115
162
135
122
105
171
135
123
126
140
123
123
102
TABLE C.43 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-168_2
Flow direction measurements
Northing
3664111
178
101
Easting
284628
178
101
Unit
QTpwu
110
98
Mean
112
123
116
Median
105
123
n
14
78
78
78
95
108
TABLE C.44 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-170_1
Flow direction measurements
Northing
3664010
108
66
Easting
284506
108
72
Unit
QTpwuc
110
72
Mean
114
105
61
Median
90
110
215
n
17
90
215
90
265
90
78
77
75
TABLE C.45 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-170_2
Flow direction measurements
Northing
3664007
206
227
148
144
125
Easting
284501
210
223
179
102
99
Unit
QTpwuc
252
204
142
108
68
Mean
141
268
222
174
113
81
Median
131
223
128
174
113
118
n
54
151
128
208
113
105
143
157
208
113
8
144
146
110
106
352
133
167
110
106
6
133
123
110
106
47
280
148
121
125
TABLE C.46 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-175_1
Flow direction measurements
Northing
3664266
113
138
93
Easting
284116
113
138
121
Unit
QTpwuc
180
138
90
Mean
131
110
157
88
Median
126
110
175
151
n
26
91
168
151
130
168
140
119
116
119
158
119
TABLE C.47 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-175_2
Flow direction measurements
Northing
3664270
126
22
Easting
284115
126
9
Unit
QTpwuc
156
9
Mean
36
358
33
Median
24
358
6
n
18
320
32
32
0
32
25
64
22
76
TABLE C.48 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-175_3
Flow direction measurements
Northing
3664270
18
10
12
Easting
284113
27
24
20
Unit
QTpwuc
30
17
49
Mean
18
30
17
51
Median
12
0
2
42
n
31
0
2
57
11
12
38
11
12
38
0
12
15
0
12
345
31
TABLE C.49 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-181_1
Flow direction measurements
Northing
3667208
141
127
118
159
150
Easting
285600
141
133
102
159
138
Unit
QTpwu
151
141
162
135
138
Mean
127
117
141
160
135
113
Median
122
116
82
173
104
111
n
58
117
108
173
96
111
148
108
107
76
123
148
100
105
105
99
148
100
122
123
99
122
109
112
123
110
122
118
112
168
127
118
157
176
TABLE C.50 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-181_2
Flow direction measurements
Northing
3667206
152
147
150
Easting
285604
163
147
147
Unit
QTpwu
163
143
147
Mean
145
171
154
178
Median
147
171
154
178
n
31
139
145
126
139
145
139
145
159
150
147
133
150
145
131
73
77
73
TABLE C.51 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197a_1
Flow direction measurements
Northing
3667269
90
0
Easting
284197
90
4
Unit
QTpwuc
88
122
Mean
77
91
Median
90
125
n
13
95
109
0
100
81
TABLE C.52 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197a_2
Flow direction measurements
Northing
3667274
265
224
Easting
284197
265
233
Unit
QTpwuc
237
207
Mean
237
237
221
Median
235
237
232
n
16
225
222
256
252
254
231
TABLE C.53 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197a_3
Flow direction measurements
Northing
3667265
73
Easting
284195
73
Unit
QTpwuc
52
Mean
31
13
Median
24
13
n
11
6
10
24
24
40
10
78
TABLE C.54 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197a_4
Flow direction measurements
Northing
3667277
11
Easting
284200
11
Unit
QTpwuc
8
Mean
13
350
Median
8
3
n
11
3
61
352
13
0
47
TABLE C.55 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197b_1
Flow direction measurements
Northing
3667278
290
258
Easting
284205
290
242
Unit
QTpwuc
240
259
Mean
256
250
262
Median
250
250
n
14
262
244
250
235
247
TABLE C.56 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-197b_1
Flow direction measurements
Northing
3667281
60
Easting
284207
61
Unit
QTpwuc
71
Mean
61
72
Median
61
50
n
8
43
43
85
79
TABLE C.57 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_1
Flow direction measurements
Northing
3666785
328
Easting
284348
328
Unit
QTpwuc
328
Mean
314
294
Median
318
294
n
10
318
318
318
318
298
TABLE C.58 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_2
Flow direction measurements
Northing
3666784
103
Easting
284342
108
Unit
QTpwuc
61
Mean
98
61
Median
103
61
n
7
147
147
TABLE C.59 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_3
Flow direction measurements
Northing
3666781
73
15
22
Easting
284343
73
92
22
Unit
QTpwuc
80
96
85
Mean
70
80
77
85
Median
74
80
77
128
n
25
74
66
74
66
52
99
52
97
71
15
80
TABLE C.60 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_4
Flow direction measurements
Northing
3666779
140
153
Easting
284343
129
157
Unit
QTpwuc
124
179
Mean
138
119
188
Median
131
119
138
n
17
131
113
129
113
116
148
148
TABLE C.61 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_5
Flow direction measurements
Northing
3666786
147
116
Easting
284354
147
116
Unit
QTpwuc
125
Mean
122
125
Median
121
117
n
12
111
102
93
125
143
TABLE C.62 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-199_6
Flow direction measurements
Northing
3666788
147
128
Easting
284353
167
128
Unit
QTpwuc
170
100
Mean
136
185
93
Median
137
160
164
n
20
152
108
150
107
140
107
143
107
125
133
81
TABLE C.63 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-236_1
Flow direction measurements
Northing
3655382
204
220
242
198
Easting
283565
204
210
235
196
Unit
QTpa
203
209
235
194
Mean
212
203
209
228
200
Median
210
203
185
228
200
n
38
200
210
215
212
234
182
215
212
198
260
215
215
192
231
211
192
219
240
TABLE C.64 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-236_2
Flow direction measurements
Northing
3655372
117
162
Easting
283566
117
102
Unit
QTpa
135
208
Mean
138
112
131
Median
133
100
176
n
20
148
110
118
113
146
141
207
142
162
108
TABLE C.65 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-242
Flow direction measurements
Northing
3655535
200
170
171
190
223
Easting
283125
200
160
171
168
180
Unit
QTpwu
159
160
190
172
120
Mean
170
159
175
160
135
228
Median
173
159
161
160
137
190
n
72
175
205
171
137
190
175
178
140
185
190
162
176
140
192
189
162
181
140
155
178
162
181
173
180
0
162
185
177
179
178
152
200
177
178
151
151
203
161
178
153
190
160
165
170
183
190
165
82
TABLE C.66 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-245b
Flow direction measurements
Northing
3656110
157
187
180
187
162
Easting
283155
150
173
185
187
162
Unit
QTpwu
167
172
186
161
167
Mean
173
167
172
168
133
185
Median
172
142
172
173
151
187
n
97
142
171
169
151
170
144
171
170
180
170
157
167
157
194
189
157
161
187
167
172
147
148
192
165
198
147
143
180
161
198
173
169
180
166
189
173
197
172
177
171
160
204
172
172
178
176
187
195
172
157
147
192
195
150
157
192
172
195
200
157
182
172
210
210
182
158
210
210
202
159
195
162
TABLE C.67 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-250b
Flow direction measurements
Northing
3654396
173
180
168
143
Easting
283542
187
180
192
143
Unit
QTpwuc
190
187
192
143
Mean
175
190
187
192
165
Median
178
198
158
172
154
n
35
174
158
184
174
188
184
177
172
184
173
178
189
189
178
137
83
TABLE C.68 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-252b
Flow direction measurements
Northing
3654368
242
182
275
275
360
Easting
283503
323
208
293
275
282
Unit
QTpwuc
320
190
83
298
282
Mean
234
322
199
56
266
282
Median
244
322
188
210
246
261
n
66
208
188
133
275
360
277
173
142
288
302
275
198
212
327
272
215
167
142
271
278
217
163
122
271
229
217
190
110
316
284
152
110
297
213
313
110
280
184
317
201
225
TABLE C.69 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-253
Flow direction measurements
Northing
3654234
59
34
85
67
Easting
283413
72
74
70
43
Unit
QTpwuc
68
74
123
34
Mean
69
62
74
52
Median
68
77
55
63
n
33
124
55
92
124
53
71
47
53
71
47
85
106
35
72
45
TABLE C.70 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-256-lower
Flow direction measurements
Northing
3654230
146
174
121
110
135
Easting
283215
148
Unit
QTpwuc
18
174
111
138
133
155
120
138
Mean
133
172
104
143
120
136
110
Median
133
n
59
194
0
118
128
110
151
187
116
147
105
114
284
128
139
91
124
284
117
136
121
118
281
110
136
133
141
0
110
134
133
138
150
115
134
96
132
150
110
135
84
TABLE C.71 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-256-upper
Flow direction measurements
Northing
3654230
148
323
69
11
28
Easting
283215
Unit
QTpwuc
175
6
29
11
26
358
25
48
11
5
Mean
36
176
25
48
11
5
Median
26
138
35
30
8
347
n
73
138
35
14
48
342
178
5
14
48
1
58
338
6
47
355
58
5
32
45
3
114
5
37
32
3
138
357
37
32
340
65
3
44
22
15
42
3
42
22
9
41
62
357
12
58
62
11
28
TABLE C.72 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-256-top
Flow direction measurements
Northing
3654227
45
80
150
Easting
283216
45
80
150
Unit
QTpwuc
38
53
Mean
93
111
72
Median
82
78
72
n
22
78
72
110
110
110
110
110
147
83
147
TABLE C.73 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-260
Flow direction measurements
Northing
3654170
68
65
61
88
114
Easting
282847
40
65
58
88
118
Unit
QTpwuc
54
62
58
82
68
Mean
64
42
50
50
78
68
Median
63
80
61
50
89
33
n
70
48
81
48
74
62
83
41
48
74
48
70
53
24
68
75
70
53
24
80
47
67
70
59
80
47
67
40
59
75
48
63
63
89
68
48
61
31
89
62
96
65
28
89
111
62
85
TABLE C.74 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-261b-lower
Flow direction measurements
Northing
3654235
42
68
108
Easting
282963
78
75
106
Unit
QTpwu
78
39
104
Mean
83
78
39
118
Median
83
34
95
155
n
26
34
105
146
33
59
103
88
103
110
40
108
TABLE C.75 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-261bupper
Flow direction measurements
Northing
3654231
167
235
200
163
182
Easting
282968
205
192
200
162
194
Unit
QTpwu
122
12
185
171
194
Mean
173
212
145
180
171
201
Median
178
204
32
180
160
201
n
60
204
32
180
175
222
208
216
189
170
222
120
132
189
165
222
208
124
219
160
172
249
126
219
156
146
249
112
170
156
146
235
168
163
156
129
TABLE C.76 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-264-1
Flow direction measurements
Northing
3654626
345
345
9
Easting
282628
345
358
346
Unit
QTpwuc
350
9
28
Mean
358
350
359
Median
358
350
359
n
23
355
3
355
3
358
3
355
8
345
9
86
TABLE C.77 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-264-2
Flow direction measurements
Northing
3654622
70
38
19
Easting
282624
43
30
19
Unit
QTpwuc
36
30
31
Mean
37
61
30
89
Median
32
61
31
22
n
30
55
10
23
35
18
5
58
25
3
46
32
53
37
32
53
TABLE C.78 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-264-3
Flow direction measurements
Northing
3654617
114
105
Easting
282627
114
82
Unit
QTpwuc
105
88
Mean
102
110
90
Median
106
110
n
14
106
106
110
95
95
TABLE C.79 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-264-4
Flow direction measurements
Northing
3654626
73
105
55
57
Easting
282623
73
98
55
57
Unit
QTpwuc
56
70
66
6
Mean
61
56
70
78
124
Median
61
72
61
73
125
n
35
72
61
24
30
58
24
45
60
64
56
65
7
56
65
7
87
TABLE C.80 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-1
Flow direction measurements
Northing
3655115
250
Easting
281619
250
Unit
QTpwu
220
Mean
222
219
Median
219
207
n
7
202
209
TABLE C.81 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-2
Flow direction measurements
Northing
3655115
346
17
Easting
281619
348
8
Unit
QTpwu
350
8
Mean
0
10
Median
357
352
n
13
350
357
357
7
7
TABLE C.82 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-3
Flow direction measurements
Northing
3655115
132
Easting
281619
132
Unit
QTpwu
116
Mean
135
116
Median
132
158
n
6
158
88
TABLE C.83 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-4
Flow direction measurements
Northing
3655115
43
9
42
23
116
Easting
281619
43
9
46
39
125
Unit
QTpwu
82
0
30
63
128
Mean
55
82
3
30
60
57
Median
41
78
3
12
52
121
n
49
38
3
23
41
0
113
22
32
153
142
358
22
32
111
125
25
35
3
180
100
25
42
23
133
TABLE C.84 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-5
Flow direction measurements
Northing
3655115
191
222
182
Easting
281619
191
222
165
Unit
QTpwu
195
214
Mean
199
204
214
Median
195
207
220
n
22
161
222
195
190
190
190
208
175
227
182
TABLE C.85 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-6
Flow direction measurements
Northing
3655115
30
57
30
Easting
281619
34
10
21
Unit
QTpwu
8
10
86
Mean
30
8
352
86
Median
11
358
0
105
n
29
5
0
81
7
11
81
6
359
75
6
359
75
34
15
89
TABLE C.86 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273a-7
Flow direction measurements
Northing
3655115
167
168
Easting
281619
158
182
Unit
QTpwu
152
210
Mean
168
179
Median
167
179
n
13
160
134
162
162
174
TABLE C.87 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-273b
Flow direction measurements
Northing
3655115
141
161
169
203
253
Easting
281613
160
161
170
203
224
Unit
QTpwu
160
147
170
241
216
Mean
191
144
168
171
184
226
Median
173
144
212
165
184
232
n
60
144
212
165
196
248
152
254
140
242
249
227
254
136
270
248
166
158
139
260
227
162
158
157
260
183
161
158
157
239
223
161
164
199
174
228
TABLE C.88 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-274
Flow direction measurements
Northing
3655070
135
202
162
173
174
Easting
Unit
281735
93
146
163
158
174
QTpwu
148
146
163
158
174
Mean
171
171
168
163
178
228
Median
174
182
168
174
178
212
n
74
182
158
174
185
212
100
148
174
185
195
120
180
174
185
205
160
180
174
202
205
118
180
173
197
154
115
180
173
197
194
119
179
172
197
189
193
175
162
166
189
193
154
162
166
175
193
154
173
155
90
TABLE C.89 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-285
Flow direction measurements
Northing
3655094
3
47
70
332
50
Easting
281358
3
52
70
330
31
Unit
QTpwu
19
52
70
358
31
Mean
18
25
64
0
320
42
Median
25
25
56
31
320
45
n
54
25
56
31
324
45
50
16
76
324
318
50
19
65
337
343
50
16
335
358
324
47
16
342
358
324
47
7
325
44
TABLE C.90 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-289-1
Flow direction measurements
Northing
3655195
157
180
158
136
153
Easting
280408
147
150
158
136
159
Unit
QTpwu
188
169
165
136
168
Mean
160
158
169
138
208
207
Median
158
145
171
138
208
136
n
54
170
180
160
131
136
180
153
124
157
136
180
153
124
140
136
173
175
184
140
136
204
144
148
195
136
180
144
182
195
TABLE C.91 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-289-2
Flow direction measurements
Northing
3655181
183
307
Easting
280418
183
307
Unit
QTpwu
183
191
Mean
228
265
191
Median
223
206
225
n
19
206
236
223
256
223
256
222
256
213
91
TABLE C.92 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-289-3
Flow direction measurements
Northing
3655181
317
325
259
Easting
280418
310
248
259
Unit
QTpwu
245
190
288
Mean
262
221
190
236
Median
253
221
221
236
n
28
222
276
314
291
258
314
290
233
314
247
233
325
242
TABLE C.93 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-289-4
Flow direction measurements
Northing
3655181
182
150
197
123
Easting
280418
182
154
197
123
Unit
QTpwu
209
186
163
254
Mean
176
172
186
159
254
Median
182
190
192
162
254
n
41
190
192
162
129
166
205
144
129
170
205
124
188
170
202
124
188
170
202
95
188
202
TABLE C.94 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290_1
Flow direction measurements
Northing
3655347
266
181
181
198
207
Easting
280105
266
195
226
198
219
Unit
QTpwu
278
195
226
183
208
Mean
214
262
206
206
183
205
Median
207
262
206
206
183
194
n
53
218
195
207
234
215
210
195
207
222
195
192
180
196
222
283
279
229
196
212
244
255
220
192
180
217
214
192
219
92
TABLE C.95 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290_2
Flow direction measurements
Northing
3655352
76
155
139
Easting
280104
76
151
146
Unit
QTpwu
77
151
119
Mean
124
108
129
147
Median
139
105
129
147
n
31
105
150
144
153
150
118
153
143
130
105
143
151
105
139
50
50
TABLE C.96 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290b
Flow direction measurements
Northing
3655358
165
70
178
119
178
Easting
280090
165
135
178
131
178
Unit
QTpwu
166
120
153
130
144
Mean
127
164
125
153
130
119
Median
130
168
103
153
101
47
n
114
168
130
142
101
38
163
173
142
10
108
167
135
129
55
108
167
135
169
66
94
182
125
111
28
74
182
194
111
78
78
175
171
97
74
77
175
123
97
92
59
177
123
97
92
59
164
143
117
131
43
236
148
117
94
42
236
93
170
85
98
220
93
172
84
148
190
109
142
98
83
185
170
145
89
83
185
212
172
89
83
70
148
103
152
88
70
162
117
152
93
TABLE C.97 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290c
Flow direction measurements
Northing
3655348
147
Easting
280078
154
Unit
QTpwu
146
Mean
156
151
Median
152
152
n
10
152
152
220
141
141
TABLE C.98 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290d-1
Flow direction measurements
Northing
3655358
212
250
Easting
280060
276
250
Unit
QTpwu
238
243
Mean
218
183
243
Median
215
183
n
14
183
183
180
215
215
TABLE C.99 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-290d-2
Flow direction measurements
Northing
3655358
156
165
151
178
Easting
280060
156
165
160
195
Unit
QTpwu
175
207
160
212
Mean
179
175
207
160
Median
183
138
195
157
n
33
183
191
157
183
192
208
183
195
208
195
193
175
195
151
190
94
TABLE C.100 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-293
Flow direction measurements
Northing
3655286
17
45
98
Easting
279628
4
45
122
Unit
QTpwuc
60
65
45
Mean
61
53
71
23
Median
59
73
71
38
n
30
43
92
38
57
92
112
15
111
114
15
103
33
67
102
15
TABLE C.101 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-294-1
Flow direction measurements
Northing
3655250
55
127
Easting
279539
56
98
Unit
QTpwuc
56
103
Mean
67
41
88
Median
56
41
32
n
19
90
32
80
32
103
359
103
25
103
TABLE C.102 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-294-2
Flow direction measurements
Northing
3655245
17
17
Easting
279536
17
17
Unit
QTpwuc
17
6
Mean
14
37
3
Median
17
37
10
n
19
5
0
5
21
5
2
15
25
17
95
TABLE C.103 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-300-1
Flow direction measurements
Northing
3654044
251
222
Easting
281651
251
170
Unit
QTpwu
268
238
Mean
245
267
253
Median
245
297
n
14
312
229
229
222
222
TABLE C.104 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-300-2
Flow direction measurements
Northing
3654045
73
103
Easting
281650
70
104
Unit
QTpwu
72
102
Mean
90
53
102
Median
102
53
102
n
21
53
140
41
119
53
130
63
130
103
130
102
TABLE C.105 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-300-3
Flow direction measurements
Northing
3654040
207
140
260
Easting
281648
196
140
213
Unit
QTpwu
196
66
245
Mean
177
129
66
255
Median
196
233
48
252
n
27
215
120
244
181
200
211
158
152
148
152
140
202
96
TABLE C.106 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-300-4
Flow direction measurements
Northing
3654053
68
66
49
Easting
281649
68
49
53
Unit
QTpwu
68
49
38
Mean
52
68
39
38
Median
56
65
33
n
24
65
78
58
26
58
26
65
23
65
28
TABLE C.107 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-300-5
Flow direction measurements
Northing
3654049
98
139
Easting
281648
98
139
Unit
QTpwu
62
110
Mean
128
125
142
Median
133
125
183
n
17
105
183
78
183
140
140
133
TABLE C.108 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-301
Flow direction measurements
Northing
3660774
141
97
173
143
355
Easting
284031
141
97
100
134
144
Unit
QTpwt
141
141
100
173
144
Mean
145
119
141
107
173
86
Median
141
119
141
107
125
86
n
80
119
116
107
125
125
154
116
141
125
125
154
123
141
242
178
154
186
211
200
138
125
90
114
200
189
125
90
114
6
96
166
90
114
6
96
166
285
297
163
95
166
220
115
170
95
166
220
115
172
220
164
220
143
172
220
97
TABLE C.109 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-305
Flow direction measurements
Northing
3660773
128
160
322
170
145
Easting
283914
128
153
105
172
145
Unit
QTpa
168
145
130
310
129
Mean
154
135
145
186
115
129
Median
145
155
145
156
118
179
n
47
155
188
156
130
96
132
140
138
148
96
132
165
138
152
185
155
110
132
160
322
110
105
TABLE C.110 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-305a
Flow direction measurements
Northing
3655346
141
0
106
218
Easting
283568
141
0
26
3
Unit
QTpa
105
24
131
157
Mean
92
105
24
131
157
Median
55
19
24
152
151
n
39
46
24
129
28
46
25
55
324
46
25
55
348
34
106
55
225
34
106
55
TABLE C.111 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-305b
Flow direction measurements
Northing
3655342
358
122
143
34
3
Easting
283567
358
140
85
121
157
Unit
QTpa
56
140
86
223
157
Mean
127
56
65
86
233
151
Median
122
151
65
186
56
28
n
48
151
65
186
56
324
151
65
105
56
348
151
44
105
56
225
122
44
27
56
122
143
34
218
98
TABLE C.112 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-306
Flow direction measurements
Northing
3655745
10
14
53
348
15
Easting
283396
10
357
350
354
18
Unit
QTpwm
6
357
353
24
18
Mean
14
41
308
346
24
310
Median
15
31
3
346
357
310
n
120
116
357
31
17
3
116
15
26
23
12
33
15
26
23
54
33
15
48
23
42
155
0
48
24
349
345
307
341
0
349
27
309
341
349
342
27
309
144
349
29
2
330
144
358
357
2
330
128
336
357
19
17
128
336
357
19
17
17
326
35
21
17
17
26
35
13
17
29
347
47
19
17
29
347
47
19
1
8
347
18
19
1
8
16
18
330
1
8
16
329
14
53
348
16
15
TABLE C.113 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-506
Flow direction measurements
Northing
3667194
239
215
137
232
233
Easting
288209
240
206
137
232
233
Unit
QTpa
197
157
199
223
233
Mean
214
219
157
206
223
227
Median
223
208
200
203
239
227
n
73
259
170
203
237
232
223
170
190
237
232
208
191
190
225
239
119
197
224
225
239
241
239
225
208
228
222
169
276
230
246
240
169
276
243
246
200
197
193
243
230
217
184
215
243
177
193
232
243
99
TABLE C.114 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-507_1
Flow direction measurements
Northing
3667240
263
227
190
Easting
288505
263
229
193
Unit
QTpa
225
229
193
Mean
213
250
227
241
Median
227
227
195
145
n
28
196
216
145
232
245
157
232
226
157
238
205
238
190
TABLE C.115 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT WS-507_2
Flow direction measurements
Northing
3667237
240
173
Easting
288496
158
155
Unit
QTpa
201
210
Mean
195
190
280
Median
184
190
280
n
16
185
151
180
180
182
170
TABLE C.116 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 130926_2
Flow direction measurements
Northing
3664345
106
145
65
51
99
Easting
284149
139
119
86
71
99
221
Unit
QTpwu
110
221
59
104
Mean
115
141
87
106
109
58
Median
106
163
84
58
184
121
n
67
96
205
144
95
104
119
134
106
102
51
116
90
109
95
71
178
74
100
96
95
146
99
121
119
102
140
163
53
159
102
159
86
79
221
190
109
106
205
154
221
104
74
100
TABLE C.117 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 131104_1-2a
Flow direction measurements
Northing
3665693
316
260
290
249
251
Easting
289828
273
306
309
321
251
Unit
QTpe
311
299
279
310
284
Mean
289
301
255
285
275
290
Median
290
264
274
341
266
290
n
66
265
298
256
265
341
291
371
249
346
281
302
251
281
291
321
310
313
246
316
265
301
284
326
273
265
268
289
321
302
276
295
323
260
315
284
266
306
321
290
269
271
TABLE C.118 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 131104_2-3d
Flow direction measurements
Northing
3663637
204
248
181
170
170
Easting
288860
156
229
196
141
173
Unit
QTpa
210
170
176
136
150
Mean
190
264
173
202
160
150
Median
185
250
140
151
210
202
n
62
250
150
194
236
151
206
206
218
131
205
189
254
156
180
141
162
239
134
198
236
166
149
256
170
198
247
256
209
249
174
154
205
210
178
138
150
250
101
TABLE C.119 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140130_1-6
Flow direction measurements
Northing
3660677
190
189
194
171
224
Easting
288290
171
213
206
189
240
Unit
QTpa
189
190
196
189
205
Mean
208
235
256
197
230
205
Median
203
230
229
206
245
191
n
84
236
234
190
176
192
245
226
175
184
192
176
215
196
184
197
170
224
174
172
190
184
240
244
173
175
230
246
216
219
196
172
198
201
219
196
250
205
216
219
201
214
245
184
213
216
234
191
175
213
184
173
210
221
256
221
219
192
190
215
TABLE C.120 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140131_2-3
Flow direction measurements
Northing
3660038
226
265
237
231
234
Easting
289206
203
176
181
262
234
Unit
QTper
201
252
254
203
171
Mean
224
244
262
299
244
182
Median
220
234
185
216
234
216
n
79
235
197
191
234
216
234
220
249
204
181
195
231
244
204
299
198
234
224
204
191
221
171
276
201
276
204
169
190
176
190
201
209
226
262
184
280
226
184
262
184
304
182
243
185
231
302
216
200
197
262
244
224
214
197
102
TABLE C.121 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140212_5
Flow direction measurements
Northing
3664312
241
249
273
270
218
Easting
289596
222
230
287
217
221
Unit
QTpe
240
239
253
255
221
Mean
250
241
266
261
230
276
Median
249
236
280
264
251
276
n
75
281
252
274
222
273
280
218
259
240
259
226
222
256
236
256
235
271
235
235
235
276
230
248
262
229
262
221
229
262
229
262
252
235
231
270
273
277
242
266
217
236
265
249
280
217
231
276
235
252
251
TABLE C.122 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140221_2-5a
Flow direction measurements
Northing
3663141
176
200
180
168
179
Easting
289032
197
138
194
194
189
Unit
Qfe
211
201
181
176
194
Mean
184
191
175
182
197
182
Median
180
219
150
203
191
176
n
77
188
171
176
170
176
203
170
170
204
170
221
176
189
228
166
170
170
166
211
178
194
141
171
200
166
184
174
181
138
181
204
171
178
175
204
196
193
166
171
168
218
179
155
176
228
189
181
170
211
162
204
141
103
TABLE C.123 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140701_2
Flow direction measurements
Northing
3661778
126
146
130
105
114
Easting
285273
126
96
130
84
114
Unit
QTpwm
101
96
130
84
84
Mean
113
101
134
130
104
84
Median
116
101
134
130
104
116
n
129
101
123
100
104
116
101
123
104
66
116
104
123
124
66
116
104
65
124
124
70
104
65
124
124
70
104
65
140
124
129
104
96
140
124
90
123
96
136
124
90
123
90
136
116
114
123
97
136
116
114
123
97
121
116
143
126
120
125
131
143
126
111
148
131
89
126
111
148
134
89
126
141
148
91
84
161
141
148
91
84
161
114
148
91
84
139
107
118
91
84
139
107
118
91
84
139
107
118
104
146
107
105
104
104
TABLE C.124 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140701_3
Flow direction measurements
Northing
3661879
121
129
115
138
109
Easting
284672
115
81
130
123
109
Unit
Qtp3
130
119
129
129
92
Mean
115
129
87
164
91
134
Median
116
116
71
120
91
144
n
127
164
71
124
156
125
120
144
140
119
125
124
94
140
129
125
140
81
135
129
125
135
95
135
81
99
124
109
124
119
95
136
110
136
87
95
111
92
111
71
95
88
134
111
71
121
131
144
88
71
89
145
125
88
71
100
127
99
131
71
100
96
95
131
144
100
109
138
145
94
100
138
121
145
81
105
123
89
145
81
105
129
100
127
81
105
91
105
127
81
109
156
109
127
95
90
121
109
95
119
121
109
95
TABLE C.125 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140701_4c
Flow direction measurements
Northing
3661404
Easting
285512
Unit
QTpwu
121
74
93
80
106
98
93
74
130
80
124
121
74
103
130
Mean
99
91
121
74
70
130
Median
93
80
124
74
66
102
n
62
71
91
93
106
66
70
71
93
80
66
66
70
86
99
106
130
66
101
109
106
78
78
139
86
99
132
78
111
139
149
149
96
139
93
93
106
96
105
TABLE C.126 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140710A_1d
Flow direction measurements
Northing
3658441
174
190
175
164
172
Easting
288821
206
171
199
164
184
Unit
QTpa
164
165
178
164
196
Mean
183
166
155
191
164
196
Median
186
186
169
160
166
200
n
89
194
171
159
186
190
166
168
196
186
170
179
199
189
186
190
201
179
198
186
187
172
199
203
194
187
184
155
168
194
190
196
194
180
194
171
200
209
183
194
165
190
201
190
179
155
170
200
174
179
169
170
204
206
201
169
190
146
206
201
171
187
174
206
201
TABLE C.127 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140710B_1d
Flow direction measurements
Northing
3658441
199
201
199
189
180
Easting
288821
199
200
199
189
180
Unit
QTpa
179
200
178
198
183
Mean
187
179
204
178
198
183
Median
190
199
204
191
203
183
n
56
199
204
160
203
183
155
146
159
203
190
155
174
159
203
190
194
174
196
168
194
175
196
168
209
175
189
180
209
199
189
180
106
TABLE C.128 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140729A_1-2a
Flow direction measurements
Northing
3660504
139
177
Easting
279820
129
164
Unit
QTpwu
123
182
Mean
142
96
165
Median
147
150
99
n
20
131
144
153
134
155
104
166
150
131
151
TABLE C.129 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140729B_1-2a
Flow direction measurements
Northing
3660504
140
141
109
Easting
279820
134
151
111
Unit
QTpwu
134
141
119
Mean
127
106
114
108
Median
127
94
125
91
n
30
191
123
96
155
134
133
98
120
166
100
165
135
136
127
126
TABLE C.130 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140730_2-1
Flow direction measurements
Northing
3659140
166
154
172
136
170
Easting
279474
150
151
154
142
117
Unit
QTpwuc
119
190
144
145
151
Mean
156
160
185
162
154
135
Median
154
184
179
174
170
184
n
49
161
141
201
197
165
171
164
140
149
146
165
124
140
152
144
173
151
130
177
151
147
161
126
134
107
TABLE C.131 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140730_2-1b
Flow direction measurements
Northing
3660074
117
140
155
152
136
Easting
278860
101
188
138
156
184
Unit
QTpwu
155
117
155
138
197
Mean
146
145
151
196
91
165
Median
148
166
135
199
110
153
n
50
153
190
128
103
150
141
150
139
108
151
136
128
116
127
156
120
169
159
132
138
166
146
124
201
154
TABLE C.132 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140730_2-1c
Flow direction measurements
Northing
3661051
93
106
124
135
149
Easting
278485
120
123
144
156
119
Unit
QTpwuc
89
125
151
137
130
Mean
133
98
126
109
110
164
Median
129
111
129
106
126
166
n
50
125
146
119
160
131
122
118
125
164
168
124
128
141
150
159
135
114
141
175
126
140
161
150
165
123
TABLE C.133 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140730_2-3
Flow direction measurements
Northing
3659005
158
150
130
161
167
Easting
279834
153
176
105
132
175
Unit
QTpwuc
164
190
82
209
208
Mean
158
184
126
136
191
216
Median
160
137
134
146
171
158
n
50
151
209
118
169
186
124
105
105
139
166
196
120
121
190
204
205
125
122
194
203
161
136
125
174
202
108
TABLE C.134 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140731A_3-3b
Flow direction measurements
Northing
3658484
146
96
Easting
283110
101
55
Unit
QTpwt
100
46
Mean
93
98
70
Median
98
65
110
n
19
71
100
108
78
110
88
144
76
104
TABLE C.135 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140731B_3-3b
Flow direction measurements
Northing
3658484
259
Easting
283110
291
Unit
QTpwt
269
Mean
262
251
Median
262
241
n
6
264
TABLE C.136 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140731A_3-4a
Flow direction measurements
Northing
3658640
131
90
Easting
281458
96
116
Unit
QTpwu
111
71
Mean
104
125
141
Median
99
85
99
n
15
91
95
91
110
108
109
TABLE C.137 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140731B_3-4a
Flow direction measurements
Northing
3658640
134
146
Easting
281458
115
120
Unit
QTpwu
135
160
Mean
135
116
159
Median
136
111
136
n
15
115
141
145
142
148
TABLE C.138 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140820_1a
Flow direction measurements
Northing
3659174
231
170
181
185
216
Easting
286970
181
204
196
201
164
Unit
Qtr4
216
242
197
178
160
Mean
171
186
176
205
199
209
Median
199
186
194
235
175
204
n
50
241
212
198
220
208
207
197
204
172
155
182
170
202
203
166
176
214
230
210
228
190
174
222
230
171
TABLE C.139 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140820_2a
Flow direction measurements
Northing
3658350
70
55
112
Easting
286010
94
104
78
Unit
QTpa
112
107
64
Mean
93
65
80
100
Median
95
95
86
103
n
25
90
83
86
99
124
121
97
82
122
103
110
TABLE C.140 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140903_1c
Flow direction measurements
Northing
3658188
154
90
166
Easting
284403
129
131
110
Unit
QTpwm
148
129
148
Mean
127
107
86
155
Median
129
98
139
109
n
25
115
128
155
175
71
172
33
180
103
112
TABLE C.141 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140903A_3
Flow direction measurements
Northing
3658315
45
27
44
Easting
283940
41
82
71
Unit
QTpwm
60
56
72
Mean
67
26
24
65
Median
65
45
92
68
n
25
63
69
80
133
109
101
61
101
100
53
TABLE C.142 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140903B_3
Flow direction measurements
Northing
3658315
72
51
39
Easting
283940
107
70
69
Unit
QTpwm
79
98
106
Mean
86
111
114
97
Median
84
51
91
110
n
25
80
84
97
83
146
92
72
81
85
56
111
TABLE C.143 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140903_4
Flow direction measurements
Northing
3657970
50
75
Easting
282858
72
103
Unit
QTpwt
52
67
Mean
77
54
98
Median
77
78
105
n
15
77
48
85
81
107
TABLE C.144 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140910_1-2c
Flow direction measurements
Northing
3657529
161
160
127
Easting
285332
145
183
148
Unit
QTpwm
174
152
198
Mean
159
146
243
124
Median
157
121
134
163
n
25
157
176
91
136
241
180
171
125
207
143
TABLE C.145 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 140930_2
Flow direction measurements
Northing
3661328
126
124
124
Easting
283002
153
197
78
Unit
QTpwu
156
116
119
Mean
129
167
148
139
Median
126
151
123
101
n
27
101
116
175
108
56
133
88
146
79
134
151
266
112
TABLE C.146 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141006A_1-1e
Flow direction measurements
Northing
3654831
112
109
236
Easting
284549
104
122
107
Unit
QTpwuc
114
150
153
Mean
97
73
41
78
Median
92
89
57
80
n
25
146
42
168
43
49
105
42
51
91
61
TABLE C.147 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141006B_1-1e
Flow direction measurements
Northing
3654831
291
109
136
Easting
284549
51
101
41
Unit
QTpwuc
111
64
41
Mean
70
51
70
75
Median
68
55
39
226
n
25
26
55
52
56
81
74
50
112
119
68
TABLE C.148 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141006_1-2b
Flow direction measurements
Northing
3655626
228
191
334
29
Easting
285250
72
180
325
18
Unit
Qtr5
41
210
229
179
Mean
214
0
153
226
182
Median
200
353
171
224
232
n
35
207
352
2
216
241
198
194
190
223
228
140
229
186
200
226
113
TABLE C.149 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141029_1e
Flow direction measurements
Northing
3664454
231
230
217
251
277
Easting
288554
250
258
192
223
240
Unit
QTpe
280
186
267
291
204
Mean
242
250
256
276
260
225
Median
243
228
198
224
274
254
n
52
212
211
255
262
219
235
220
291
276
235
222
269
243
253
250
244
212
271
229
216
215
257
206
213
242
291
270
TABLE C.150 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141029_3
Flow direction measurements
Northing
3665004
266
267
281
250
Easting
288726
245
260
289
261
Unit
QTpe
251
240
292
312
Mean
254
250
241
274
Median
251
256
286
251
n
33
264
223
247
226
199
264
218
209
249
265
251
284
244
218
256
TABLE C.151 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141029_4e
Flow direction measurements
Northing
3665863
294
2
232
350
312
Easting
289977
331
319
285
316
266
Unit
QTpe
332
286
304
305
320
Mean
306
309
275
333
314
322
Median
307
309
321
320
266
304
n
56
348
291
336
267
266
310
355
310
281
344
279
294
270
359
341
227
335
281
274
252
330
294
250
348
329
1
244
349
297
321
273
114
TABLE C.152 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141107_1c
Flow direction measurements
Northing
3658842
199
170
226
190
164
Easting
287595
174
163
167
179
176
Unit
QTper
177
195
235
215
205
Mean
182
160
165
194
152
170
Median
179
161
174
157
181
n
44
194
159
172
151
134
185
149
204
180
153
179
184
178
206
203
209
177
218
215
202
TABLE C.153 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141107_3
Flow direction measurements
Northing
3658275
190
178
205
153
150
Easting
289680
218
281
220
197
206
Unit
QTper
224
274
195
211
211
Mean
197
214
270
197
208
222
Median
199
188
179
255
148
204
n
52
204
270
161
124
194
206
184
169
200
225
226
241
170
181
182
157
201
129
179
154
216
155
146
150
231
159
210
TABLE C.154 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141107_3b
Flow direction measurements
Northing
3657907
226
268
196
181
Easting
289205
256
204
174
200
Unit
QTper
222
199
178
Mean
217
209
194
158
Median
218
243
200
219
n
32
233
250
240
225
244
218
206
180
237
218
216
251
249
179
259
115
TABLE C.155 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141107_5b
Flow direction measurements
Northing
3658043
246
162
193
Easting
288894
234
205
169
Unit
QTper
187
213
179
Mean
210
175
217
215
Median
216
233
256
n
24
249
176
190
190
236
221
230
223
220
225
TABLE C.156 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141120_1-2b
Flow direction measurements
Northing
3656912
182
194
241
Easting
289696
246
224
201
Unit
QTpef
250
227
209
Mean
228
216
176
254
Median
231
254
264
263
n
26
170
249
251
284
250
222
247
234
186
219
211
TABLE C.157 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141120_1-3a
Flow direction measurements
Northing
3656175
220
203
234
225
177
Easting
289068
180
174
181
255
210
Unit
QTpa
219
186
208
216
209
Mean
212
184
156
193
194
175
Median
212
226
250
228
207
244
n
52
259
263
218
248
214
181
275
194
212
195
204
214
223
224
241
180
244
211
249
173
249
241
209
191
149
226
189
116
TABLE C.158 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141120_1-3d
Flow direction measurements
Northing
3655928
264
236
278
Easting
289499
223
214
236
Unit
QTpe
296
212
268
Mean
244
314
207
272
Median
236
246
268
285
n
25
232
200
200
227
239
200
266
204
267
234
TABLE C.159 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141120_1-4d
Flow direction measurements
Northing
3655667
245
217
241
Easting
288860
238
160
195
Unit
QTpa
245
149
207
Mean
213
203
210
164
Median
211
294
161
265
n
26
249
175
250
226
212
266
252
149
174
205
173
TABLE C.160 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141121_2-1a
Flow direction measurements
Northing
3653893
200
179
221
Easting
287664
226
172
246
Unit
Qtr4
222
211
221
Mean
213
210
229
220
Median
219
234
209
184
n
26
187
249
223
246
198
221
191
187
217
225
212
117
TABLE C.161 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141121_2-3
Flow direction measurements
Northing
3653878
291
261
Easting
288948
0
294
Unit
QTpe
281
300
Mean
298
310
262
Median
294
332
310
n
21
325
314
279
280
294
307
268
312
318
270
290
TABLE C.162 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141121_2-4b
Flow direction measurements
Northing
3654682
218
231
195
Easting
288642
240
249
184
Unit
QTpe
254
265
216
Mean
225
241
258
220
Median
220
246
239
196
n
25
260
206
197
217
249
208
210
194
204
230
TABLE C.163 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141121_2-5
Flow direction measurements
Northing
3656265
174
223
180
205
180
Easting
288458
194
193
195
195
140
Unit
QTpa
202
181
196
187
168
Mean
188
220
205
184
210
186
Median
191
230
179
225
200
174
n
57
205
166
210
194
186
197
164
141
208
191
210
199
202
190
155
203
171
206
136
176
177
180
161
156
194
191
146
181
221
143
211
192
118
TABLE C.164 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141126_1c
Flow direction measurements
Northing
3657356
146
157
Easting
281208
168
127
Unit
QTpwuc
155
158
Mean
157
115
191
Median
155
179
152
n
15
155
180
149
177
150
TABLE C.165 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141126_1h
Flow direction measurements
Northing
3657938
191
254
180
Easting
281894
174
241
173
Unit
QTpwu
233
211
156
Mean
211
224
246
231
Median
213
187
251
221
n
25
209
195
213
220
236
181
200
221
222
206
TABLE C.166 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 141126_5a
Flow direction measurements
Northing
3657195
87
136
154
127
Easting
283808
111
135
98
129
Unit
QTpwm
114
159
61
Mean
107
96
96
96
Median
104
85
139
95
n
32
113
120
84
98
97
124
102
105
91
76
128
111
64
104
103
119
TABLE C.167 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150127_1a
Flow direction measurements
Northing
3654549
266
Easting
288313
254
Unit
Qfe
233
Mean
250
279
Median
252
234
n
10
261
271
226
227
249
TABLE C.168 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150127_1e
Flow direction measurements
Northing
3654223
194
Easting
287905
224
Unit
Qfe
240
Mean
208
210
Median
202
194
n
6
185
TABLE C.169 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150127A_3a
Flow direction measurements
Northing
3655754
137
132
252
255
Easting
283427
182
220
185
218
Unit
QTpa
112
110
252
60
Mean
206
150
140
207
335
Median
214
185
42
212
n
34
265
216
282
350
88
260
125
60
350
350
240
281
118
234
277
120
TABLE C.170 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150127B_3a
Flow direction measurements
Northing
3655754
197
270
Easting
283427
207
251
Unit
QTpa
210
245
Mean
231
253
237
Median
239
232
240
n
16
258
247
270
75
200
140
TABLE C.171 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317A_1-1b
Flow direction measurements
Northing
3656535
51
65
51
Easting
280032
17
343
61
Unit
QTpwuc
17
33
25
Mean
35
45
64
25
Median
41
29
40
90
n
25
136
41
336
54
336
46
330
64
318
64
TABLE C.172 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317B_1-1b
Flow direction measurements
Northing
3656535
59
92
Easting
280032
39
160
Unit
QTpwuc
163
144
Mean
119
163
144
Median
160
163
180
n
19
356
254
356
126
356
126
168
356
92
121
TABLE C.173 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317A_1-1d
Flow direction measurements
Northing
3656426
154
116
179
Easting
280793
154
153
206
Unit
QTpwuc
203
131
232
Mean
183
203
90
232
Median
188
203
185
120
n
25
148
233
194
233
194
210
143
185
188
239
TABLE C.174 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317B_1-1d
Flow direction measurements
Northing
3656426
182
119
140
Easting
280793
120
98
109
Unit
QTpwuc
70
103
181
Mean
123
178
136
160
Median
119
125
97
114
n
25
141
97
168
97
145
196
86
64
104
64
TABLE C.175 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317C_1-1d
Flow direction measurements
Northing
3656426
268
310
269
Easting
280793
254
319
232
Unit
QTpwuc
254
287
232
Mean
266
181
287
224
Median
268
179
249
209
n
27
272
330
172
327
303
129
290
295
266
295
266
324
122
TABLE C.176 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317_1-1e
Flow direction measurements
Northing
3656392
80
324
115
74
5
Easting
280984
80
324
75
60
5
Unit
QTpwuc
95
62
113
28
11
Mean
64
134
36
78
38
30
Median
74
45
65
138
38
30
n
45
120
11
55
110
120
11
20
110
58
11
20
110
106
141
78
44
118
129
74
30
TABLE C.177 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317A_1-2a
Flow direction measurements
Northing
3657254
31
81
Easting
280863
31
175
Unit
QTpwuc
103
26
Mean
58
123
23
Median
51
123
23
n
20
150
23
76
339
92
339
70
344
171
12
TABLE C.178 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317B_1-2a
Flow direction measurements
Northing
3657254
122
150
Easting
280863
104
320
Unit
QTpwuc
86
50
Mean
84
71
50
Median
83
92
120
n
16
92
79
56
56
139
66
123
TABLE C.179 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317_1-2d
Flow direction measurements
Northing
3656534
121
56
79
Easting
281488
71
189
131
Unit
QTpwuc
71
189
92
Mean
99
59
119
43
Median
96
100
119
87
n
30
15
161
87
124
197
99
124
211
33
101
226
68
64
79
50
TABLE C.180 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317_1-2g
Flow direction measurements
Northing
3656882
60
74
71
31
106
Easting
282039
60
81
78
36
96
Unit
QTpwuc
60
28
83
81
110
Mean
74
64
112
83
113
134
Median
76
11
112
116
136
134
n
54
26
112
115
11
106
26
73
124
8
89
68
108
100
8
80
68
86
27
71
64
17
113
26
14
107
55
71
26
106
TABLE C.181 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317A_1-3c
Flow direction measurements
Northing
3655400
74
54
138
Easting
281765
74
14
148
Unit
QTpwu
36
14
148
Mean
71
110
14
148
Median
74
74
80
72
n
31
74
105
58
34
114
18
81
123
18
81
89
33
54
82
49
124
41
TABLE C.182 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317B_1-3c
Flow direction measurements
Northing
3655400
153
109
161
Easting
281765
125
66
152
Unit
QTpwuc
212
127
139
Mean
140
212
185
139
Median
146
81
119
139
n
25
96
119
156
110
149
156
149
156
146
156
TABLE C.183 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317A_1-3e
Flow direction measurements
Northing
3655587
124
Easting
281301
69
Unit
QTpwuc
91
Mean
106
81
Median
92
86
n
10
86
92
127
153
153
TABLE C.184 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317B_1-3e
Flow direction measurements
Northing
3655587
144
Easting
281301
101
Unit
QTpwuc
76
Mean
129
76
Median
134
156
n
10
201
173
99
134
134
125
TABLE C.185 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317_1-4g
Flow direction measurements
Northing
3654381
53
114
Easting
284187
85
132
59
Unit
QTpwu
85
132
107
Mean
100
130
94
74
Median
104
130
70
118
n
30
129
139
118
129
139
34
104
78
66
127
104
86
139
70
55
82
TABLE C.186 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150317_1-4h
Flow direction measurements
Northing
3654395
32
24
95
60
79
Easting
284139
78
24
114
60
22
Unit
QTpwu
56
68
34
60
70
Mean
55
41
68
34
29
66
Median
60
6
64
34
29
66
n
45
6
84
48
75
46
84
98
34
46
84
23
94
4
109
61
94
35
59
61
14
TABLE C.187 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150318A_2-3b
Flow direction measurements
Northing
3655058
186
221
Easting
288815
186
192
Unit
QTpa
186
172
Mean
205
204
135
Median
206
231
209
n
20
204
209
204
207
204
220
228
216
234
246
126
TABLE C.188 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150318B_2-3b
Flow direction measurements
Northing
3655058
196
Easting
288815
184
Unit
QTpa
250
Mean
185
177
Median
185
174
n
10
71
71
241
199
185
TABLE C.189 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150318_2-4d
Flow direction measurements
Northing
3660342
309
267
Easting
288328
331
350
Unit
QTpe
275
282
Mean
308
275
282
Median
311
274
318
n
20
330
318
330
286
330
310
344
286
344
312
TABLE C.190 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150318_2-5d
Flow direction measurements
Northing
3653934
174
188
266
221
171
Easting
285119
189
165
248
249
189
Unit
QTpa
186
167
240
220
201
215
Mean
195
189
155
280
220
Median
192
158
188
280
161
n
44
234
195
169
173
236
194
169
138
218
200
169
116
255
200
133
149
198
200
221
171
127
TABLE C.191 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150318_2-5h
Flow direction measurements
Northing
3654214
81
80
65
Easting
284776
81
80
50
Unit
QTpwuc
60
31
66
Mean
43
18
31
359
Median
31
18
33
31
n
31
73
50
31
75
11
12
50
11
12
5
29
31
5
29
95
95
TABLE C.192 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150408_2
Flow direction measurements
Northing
3667417
177
Easting
290218
177
Unit
Qtr3
196
Mean
194
187
Median
193
204
n
10
172
220
210
210
189
TABLE C.193 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_1
Flow direction measurements
Northing
3662874
134
135
184
Easting
284569
142
151
146
Unit
QTpwm
142
151
177
Mean
140
100
182
137
Median
141
86
182
201
n
30
71
56
140
171
56
140
63
170
162
134
170
116
84
184
106
128
TABLE C.194 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_1b
Flow direction measurements
Northing
3662873
144
156
151
Easting
284549
111
156
149
Unit
QTpwu
122
151
141
Mean
139
171
167
139
Median
143
171
147
105
n
30
171
113
105
148
96
112
195
125
139
195
131
49
106
152
130
TABLE C.195 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_1e
Flow direction measurements
Northing
3663131
161
153
164
Easting
284396
153
180
164
Unit
QTpwuc
153
126
125
Mean
142
127
136
131
Median
137
152
126
197
n
28
152
121
166
131
111
167
131
111
95
126
137
153
137
TABLE C.196 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_2b
Flow direction measurements
Northing
3655824
126
183
188
Easting
283890
118
156
202
Unit
QTpwmc
135
109
131
Mean
144
135
109
99
Median
131
98
228
123
n
27
216
228
123
204
111
123
165
111
86
115
149
188
129
TABLE C.197 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_2e
Flow direction measurements
Northing
3656039
211
165
182
Easting
283943
211
172
135
Unit
QTpa
140
143
175
Mean
173
190
174
158
Median
174
174
243
158
n
25
176
161
167
161
182
217
182
185
134
152
TABLE C.198 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_2i
Flow direction measurements
Northing
3655494
195
142
168
Easting
283871
174
184
191
Unit
QTpa
159
184
199
Mean
181
190
194
215
Median
188
190
166
166
n
30
190
216
195
190
192
155
156
186
155
156
186
201
142
200
201
TABLE C.199 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_3
Flow direction measurements
Northing
3662393
42
216
129
Easting
284860
92
216
169
Unit
QTpwu
92
216
151
Mean
156
211
176
175
Median
161
176
150
188
n
25
144
163
141
192
161
65
176
65
156
134
130
TABLE C.200 IMBRICATION PALEOCURRENT MEASUREMENTS AT WAYPOINT 150501_4
Flow direction measurements
Northing
3667457
140
164
160
180
Easting
286478
151
210
158
170
Unit
QTpwl
139
192
180
210
Mean
173
157
156
180
210
Median
170
157
133
145
118
n
39
145
146
200
158
203
178
200
203
205
168
200
203
175
168
146
203
175
200
146
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APPENDIX D
Radiocarbon calibration data from the Williamsburg 7.5’ quadrangle
This appendix contains radiocarbon age calibration plots from three charcoal samples collected from Holocene
deposits along Cañada Honda. All data are from AMS analyses performed by Beta Analytic Inc., Miami, FL.
Calibrated 2σ age ranges determined using the Intcal13 calibration curve of Reimer et al. (2013) are given in Table 1.
Figure D.1. Calibration curve for sample WS-204 (unit Qayi). Age given in upper left is conventional age (14C yr BP).
Figure D.2. Calibration curve for sample WS-203 (unit Qfay). Age given in upper left is conventional age (14C yr
BP).
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Figure D.3. Calibration curve for sample WS-202D (unit Qfay). Age given in upper left is conventional age (14C yr
BP).
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